diff --git a/app/build.gradle b/app/build.gradle
index 5bbd1bc63..9e34ab64d 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -38,6 +38,7 @@ android {
           passing the following argument to the test runner: disableAnalytics "true".
          */
         testInstrumentationRunnerArguments disableAnalytics: 'true'
+        vectorDrawables.useSupportLibrary = true
     }
 
     buildTypes {
diff --git a/app/src/full/java/org/fdroid/fdroid/nearby/SwapWorkflowActivity.java b/app/src/full/java/org/fdroid/fdroid/nearby/SwapWorkflowActivity.java
index 3acc54758..64f210bad 100644
--- a/app/src/full/java/org/fdroid/fdroid/nearby/SwapWorkflowActivity.java
+++ b/app/src/full/java/org/fdroid/fdroid/nearby/SwapWorkflowActivity.java
@@ -1,7 +1,6 @@
 package org.fdroid.fdroid.nearby;
 
 import android.annotation.TargetApi;
-import androidx.appcompat.app.AppCompatActivity;
 import android.bluetooth.BluetoothAdapter;
 import android.content.BroadcastReceiver;
 import android.content.ComponentName;
diff --git a/app/src/full/res/layout-sw480dp/start_swap_header.xml b/app/src/full/res/layout-sw480dp/start_swap_header.xml
index 049c2d4fe..2789b8ae1 100644
--- a/app/src/full/res/layout-sw480dp/start_swap_header.xml
+++ b/app/src/full/res/layout-sw480dp/start_swap_header.xml
@@ -1,7 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout
         xmlns:android="http://schemas.android.com/apk/res/android"
-        xmlns:tools="http://schemas.android.com/tools"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
         android:id="@+id/header"
         android:layout_width="match_parent"
         android:layout_height="130dp"
@@ -12,7 +13,7 @@
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             android:scaleType="centerCrop"
-            android:src="@drawable/swap_start_header"/>
+            app:srcCompat="@drawable/swap_start_header"/>
 
     <TextView
             android:layout_width="wrap_content"
diff --git a/app/src/full/res/layout-v11/select_local_apps_list_item.xml b/app/src/full/res/layout-v11/select_local_apps_list_item.xml
index c3eac8226..d3759fb37 100644
--- a/app/src/full/res/layout-v11/select_local_apps_list_item.xml
+++ b/app/src/full/res/layout-v11/select_local_apps_list_item.xml
@@ -13,10 +13,11 @@
 -->
 
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
-    android:minHeight="?android:attr/listPreferredItemHeight"
+    android:minHeight="?attr/listPreferredItemHeight"
     android:paddingBottom="2dip"
     android:paddingTop="2dip">
 
@@ -25,7 +26,7 @@
         android:layout_width="48dip"
         android:layout_height="48dip"
         android:layout_marginLeft="?attr/listPreferredItemPaddingLeft"
-        android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+        android:layout_marginStart="?attr/listPreferredItemPaddingStart"
         android:layout_marginTop="6dip"
         android:layout_alignParentStart="true"
         android:layout_alignParentLeft="true"
@@ -38,12 +39,12 @@
         android:layout_width="32dip"
         android:layout_height="32dip"
         android:layout_marginRight="?attr/listPreferredItemPaddingLeft"
-        android:layout_marginEnd="?android:attr/listPreferredItemPaddingStart"
+        android:layout_marginEnd="?attr/listPreferredItemPaddingStart"
         android:layout_alignParentRight="true"
         android:layout_alignParentEnd="true"
         android:layout_centerVertical="true"
         tools:suppress="InconsistentLayout"
-        android:src="@drawable/ic_add_circle_outline" />
+        app:srcCompat="@drawable/ic_add_circle_outline" />
 
     <TwoLineListItem
         android:layout_toRightOf="@android:id/icon"
@@ -59,7 +60,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_marginLeft="?attr/listPreferredItemPaddingLeft"
-            android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+            android:layout_marginStart="?attr/listPreferredItemPaddingStart"
             android:layout_marginTop="6dip"
             android:textAppearance="?android:attr/textAppearanceMedium"
             tools:text="F-Droid" />
diff --git a/app/src/full/res/layout-v17/select_local_apps_list_item.xml b/app/src/full/res/layout-v17/select_local_apps_list_item.xml
index 47c96f43f..2c41d775e 100644
--- a/app/src/full/res/layout-v17/select_local_apps_list_item.xml
+++ b/app/src/full/res/layout-v17/select_local_apps_list_item.xml
@@ -13,10 +13,11 @@
 -->
 
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
-    android:minHeight="?android:attr/listPreferredItemHeight"
+    android:minHeight="?attr/listPreferredItemHeight"
     android:paddingBottom="2dip"
     android:paddingTop="2dip">
 
@@ -24,7 +25,7 @@
         android:id="@android:id/icon"
         android:layout_width="48dip"
         android:layout_height="48dip"
-        android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+        android:layout_marginStart="?attr/listPreferredItemPaddingStart"
         android:layout_marginTop="6dip"
         android:layout_alignParentStart="true"
         tools:src="@drawable/ic_launcher"
@@ -35,11 +36,11 @@
         android:id="@+id/checked"
         android:layout_width="32dip"
         android:layout_height="32dip"
-        android:layout_marginEnd="?android:attr/listPreferredItemPaddingStart"
+        android:layout_marginEnd="?attr/listPreferredItemPaddingStart"
         android:layout_alignParentEnd="true"
         android:layout_centerVertical="true"
         tools:suppress="InconsistentLayout"
-        android:src="@drawable/ic_add_circle_outline" />
+        app:srcCompat="@drawable/ic_add_circle_outline" />
 
     <TwoLineListItem
         android:layout_toEndOf="@android:id/icon"
@@ -52,7 +53,7 @@
             android:id="@+id/application_label"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
-            android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+            android:layout_marginStart="?attr/listPreferredItemPaddingStart"
             android:layout_marginTop="6dip"
             android:textAppearance="?android:attr/textAppearanceMedium"
             tools:text="F-Droid" />
diff --git a/app/src/full/res/layout/main_tab_swap.xml b/app/src/full/res/layout/main_tab_swap.xml
index 83f4926b5..39d4772b1 100644
--- a/app/src/full/res/layout/main_tab_swap.xml
+++ b/app/src/full/res/layout/main_tab_swap.xml
@@ -11,7 +11,7 @@
             android:id="@+id/image"
             android:layout_width="0dp"
             android:layout_height="0dp"
-            android:src="@drawable/nearby_splash"
+            app:srcCompat="@drawable/nearby_splash"
             android:importantForAccessibility="no"
             app:layout_constraintRight_toRightOf="parent"
             app:layout_constraintLeft_toLeftOf="parent"
diff --git a/app/src/full/res/layout/select_local_apps_list_item.xml b/app/src/full/res/layout/select_local_apps_list_item.xml
index b7f0fdda2..d51888272 100644
--- a/app/src/full/res/layout/select_local_apps_list_item.xml
+++ b/app/src/full/res/layout/select_local_apps_list_item.xml
@@ -16,7 +16,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
-    android:minHeight="?android:attr/listPreferredItemHeight"
+    android:minHeight="?attr/listPreferredItemHeight"
     android:paddingBottom="2dip"
     android:paddingTop="2dip">
 
@@ -25,7 +25,7 @@
         android:layout_width="48dip"
         android:layout_height="48dip"
         android:layout_marginLeft="?attr/listPreferredItemPaddingLeft"
-        android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+        android:layout_marginStart="?attr/listPreferredItemPaddingStart"
         android:layout_marginTop="6dip"
         android:layout_alignParentStart="true"
         android:layout_alignParentLeft="true"
@@ -37,7 +37,7 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginLeft="?attr/listPreferredItemPaddingLeft"
-        android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+        android:layout_marginStart="?attr/listPreferredItemPaddingStart"
         android:layout_alignParentRight="true"
         android:layout_alignParentEnd="true"
         android:layout_centerVertical="true" />
@@ -56,7 +56,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_marginLeft="?attr/listPreferredItemPaddingLeft"
-            android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+            android:layout_marginStart="?attr/listPreferredItemPaddingStart"
             android:layout_marginTop="6dip"
             android:textAppearance="?android:attr/textAppearanceMedium"
             tools:text="F-Droid" />
diff --git a/app/src/full/res/layout/swap_app_list_item.xml b/app/src/full/res/layout/swap_app_list_item.xml
index 0a8261475..baa27d0a4 100644
--- a/app/src/full/res/layout/swap_app_list_item.xml
+++ b/app/src/full/res/layout/swap_app_list_item.xml
@@ -4,7 +4,7 @@
         xmlns:tools="http://schemas.android.com/tools"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:minHeight="?android:attr/listPreferredItemHeight"
+        android:minHeight="?attr/listPreferredItemHeight"
         android:paddingBottom="2dip"
         android:paddingTop="2dip">
 
@@ -12,7 +12,7 @@
             android:id="@android:id/icon"
             android:layout_width="48dip"
             android:layout_height="48dip"
-            android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+            android:layout_marginStart="?attr/listPreferredItemPaddingStart"
             android:layout_marginLeft="10dp"
             android:layout_marginTop="6dip"
             android:layout_alignParentStart="true"
@@ -28,7 +28,7 @@
             android:layout_centerInParent="true"
             android:orientation="vertical"
             android:gravity="end"
-            android:layout_marginEnd="?android:attr/listPreferredItemPaddingEnd"
+            android:layout_marginEnd="?attr/listPreferredItemPaddingEnd"
             android:layout_marginRight="10dp">
 
         <Button
@@ -68,7 +68,7 @@
             android:layout_toLeftOf="@+id/button_or_text"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
-            android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+            android:layout_marginStart="?attr/listPreferredItemPaddingStart"
             android:layout_marginLeft="10dp"
             android:layout_marginTop="6dip"
             android:layout_marginBottom="6dip"
diff --git a/app/src/full/res/layout/swap_confirm_receive.xml b/app/src/full/res/layout/swap_confirm_receive.xml
index f7bfd49aa..cc7b1dd20 100644
--- a/app/src/full/res/layout/swap_confirm_receive.xml
+++ b/app/src/full/res/layout/swap_confirm_receive.xml
@@ -14,7 +14,7 @@
 
     <ImageView
             android:id="@+id/icon"
-            android:src="@drawable/ic_launcher"
+            swap:srcCompat="@drawable/ic_launcher"
             android:contentDescription="@string/icon"
             android:layout_alignParentTop="true"
             android:layout_width="117.6dp"
diff --git a/app/src/full/res/layout/swap_join_wifi.xml b/app/src/full/res/layout/swap_join_wifi.xml
index 9a123b687..7c336e63b 100644
--- a/app/src/full/res/layout/swap_join_wifi.xml
+++ b/app/src/full/res/layout/swap_join_wifi.xml
@@ -25,7 +25,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:id="@+id/wifi_icon"
-            android:src="@drawable/ic_wifi"
+            swap:srcCompat="@drawable/ic_wifi"
             android:layout_below="@+id/text_description"
             android:layout_centerHorizontal="true"/>
 
diff --git a/app/src/full/res/layout/swap_nfc.xml b/app/src/full/res/layout/swap_nfc.xml
index 2d116a234..ac2065e1a 100644
--- a/app/src/full/res/layout/swap_nfc.xml
+++ b/app/src/full/res/layout/swap_nfc.xml
@@ -14,7 +14,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:id="@+id/icon_nfc"
-            android:src="@drawable/nfc_touch"
+            swap:srcCompat="@drawable/nfc_touch"
             android:layout_alignParentTop="true"
             android:layout_centerHorizontal="true"/>
 
diff --git a/app/src/full/res/layout/swap_peer_list_item.xml b/app/src/full/res/layout/swap_peer_list_item.xml
index f98549b53..5e0a4f319 100644
--- a/app/src/full/res/layout/swap_peer_list_item.xml
+++ b/app/src/full/res/layout/swap_peer_list_item.xml
@@ -14,13 +14,13 @@
             android:layout_width="32dp"
             android:layout_height="32dp"
             android:layout_marginLeft="?attr/listPreferredItemPaddingLeft"
-            android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+            android:layout_marginStart="?attr/listPreferredItemPaddingStart"
             android:layout_gravity="center_vertical">
 
         <ImageView
                 android:layout_width="match_parent"
                 android:layout_height="match_parent"
-                android:src="@drawable/circle"
+                app:srcCompat="@drawable/circle"
                 app:tint="@color/swap_light_grey_icon"/>
 
         <ImageView
@@ -38,7 +38,7 @@
             android:layout_height="wrap_content"
             android:layout_gravity="center_vertical"
             android:layout_marginLeft="?attr/listPreferredItemPaddingLeft"
-            android:layout_marginStart="?android:attr/listPreferredItemPaddingStart"
+            android:layout_marginStart="?attr/listPreferredItemPaddingStart"
             android:textSize="20sp"
             android:textAppearance="?android:attr/textAppearanceMedium"
             tools:text="Nexus 4"/>
diff --git a/app/src/full/res/layout/swap_start_swap.xml b/app/src/full/res/layout/swap_start_swap.xml
index eec69f06f..6fdc72f0d 100644
--- a/app/src/full/res/layout/swap_start_swap.xml
+++ b/app/src/full/res/layout/swap_start_swap.xml
@@ -26,7 +26,7 @@
                 android:layout_width="24dp"
                 android:layout_height="24dp"
                 android:contentDescription="@string/use_bluetooth"
-                android:src="@drawable/ic_bluetooth_searching"/>
+                swap:srcCompat="@drawable/ic_bluetooth_searching"/>
 
         <LinearLayout
                 android:layout_width="0dp"
@@ -74,7 +74,7 @@
                 android:layout_width="24dp"
                 android:layout_height="24dp"
                 android:contentDescription="@string/wifi"
-                android:src="@drawable/ic_wifi"/>
+                swap:srcCompat="@drawable/ic_wifi"/>
 
         <LinearLayout
                 android:layout_width="0dp"
diff --git a/app/src/full/res/values-v17/styles.xml b/app/src/full/res/values-v17/styles.xml
index e2bb070aa..fc99bc544 100644
--- a/app/src/full/res/values-v17/styles.xml
+++ b/app/src/full/res/values-v17/styles.xml
@@ -4,7 +4,7 @@
     <style name="SwapTheme.AppList.SwapSuccess" parent="SwapTheme.AppList.SwapSuccessBase">
         <item name="android:textAlignment">center</item>
         <item name="android:gravity">center</item>
-        <item name="android:fontFamily">sans-serif-light</item>
+        <item name="fontFamily">sans-serif-light</item>
     </style>
 
     <style name="SwapTheme.AppList.SwapSuccessDetails" parent="SwapTheme.AppList.SwapSuccessDetailsBase">
@@ -23,7 +23,7 @@
     </style>
 
     <style name="SwapTheme.Wizard.MainText" parent="SwapTheme.Wizard.MainTextBase">
-        <item name="android:fontFamily">sans-serif-light</item>
+        <item name="fontFamily">sans-serif-light</item>
     </style>
 
 </resources>
diff --git a/app/src/full/res/values-v21/styles.xml b/app/src/full/res/values-v21/styles.xml
index 4f1c6edae..afcf90b9f 100644
--- a/app/src/full/res/values-v21/styles.xml
+++ b/app/src/full/res/values-v21/styles.xml
@@ -2,7 +2,7 @@
 <resources>
 
     <style name="SwapTheme.Wizard" parent="Theme.AppCompat.Light.NoActionBar">
-        <item name="android:colorButtonNormal">#04b9e6</item>
+        <item name="colorButtonNormal">#04b9e6</item>
     </style>
 
 </resources>
diff --git a/app/src/full/res/values/styles.xml b/app/src/full/res/values/styles.xml
index ea34ac0f7..100ef3bb4 100644
--- a/app/src/full/res/values/styles.xml
+++ b/app/src/full/res/values/styles.xml
@@ -8,7 +8,7 @@
     </style>
 
     <style name="SwapTheme.StartSwap" parent="AppThemeLight">
-        <item name="android:background">@android:color/white</item>
+        <item name="background">@android:color/white</item>
     </style>
 
     <style name="SwapTheme.StartSwap.Text" parent="@style/SwapTheme.StartSwap">
diff --git a/app/src/main/java/com/google/zxing/integration/android/IntentIntegrator.java b/app/src/main/java/com/google/zxing/integration/android/IntentIntegrator.java
index f15883dc7..37dfa815f 100644
--- a/app/src/main/java/com/google/zxing/integration/android/IntentIntegrator.java
+++ b/app/src/main/java/com/google/zxing/integration/android/IntentIntegrator.java
@@ -16,7 +16,6 @@
 
 package com.google.zxing.integration.android;
 
-import android.app.AlertDialog;
 import android.content.ActivityNotFoundException;
 import android.content.DialogInterface;
 import android.content.Intent;
@@ -26,6 +25,7 @@ import android.net.Uri;
 import android.os.Bundle;
 import android.util.Log;
 
+import androidx.appcompat.app.AlertDialog;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.fragment.app.Fragment;
 
@@ -336,7 +336,7 @@ public class IntentIntegrator {
      * @param intent Intent to start.
      * @param code Request code for the activity
      * @see android.app.AppCompatActivity#startActivityForResult(Intent, int)
-     * @see android.app.Fragment#startActivityForResult(Intent, int)
+     * @see Fragment#startActivityForResult(Intent, int)
      */
     protected void startActivityForResult(Intent intent, int code) {
         if (fragment == null) {
diff --git a/app/src/main/java/org/fdroid/fdroid/views/main/SettingsView.java b/app/src/main/java/org/fdroid/fdroid/views/main/SettingsView.java
index 5aa71206c..91cc7d1b9 100644
--- a/app/src/main/java/org/fdroid/fdroid/views/main/SettingsView.java
+++ b/app/src/main/java/org/fdroid/fdroid/views/main/SettingsView.java
@@ -77,7 +77,7 @@ public class SettingsView extends FrameLayout {
         currentTransaction.remove(existingFragment);
         currentTransaction.commitAllowingStateLoss();
         currentTransaction = null;
-        activity.getFragmentManager().executePendingTransactions();
+        activity.getSupportFragmentManager().executePendingTransactions();
     }
 
 }
diff --git a/app/src/main/res/layout-v11/app_permission_item.xml b/app/src/main/res/layout-v11/app_permission_item.xml
index 7fd230b19..328c62c4f 100644
--- a/app/src/main/res/layout-v11/app_permission_item.xml
+++ b/app/src/main/res/layout-v11/app_permission_item.xml
@@ -24,7 +24,7 @@
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:orientation="horizontal"
-    android:background="?android:attr/selectableItemBackground">
+    android:background="?attr/selectableItemBackground">
 
     <ImageView
         android:id="@+id/perm_icon"
@@ -40,7 +40,7 @@
     <ImageView
         android:layout_width="wrap_content"
         android:layout_height="match_parent"
-        android:background="?android:attr/dividerVertical" />
+        android:background="?attr/dividerVertical" />
 
     <TextView
         android:id="@+id/perm_name"
diff --git a/app/src/main/res/layout-v11/install_confirm.xml b/app/src/main/res/layout-v11/install_confirm.xml
index 111345dc3..dc599a42f 100644
--- a/app/src/main/res/layout-v11/install_confirm.xml
+++ b/app/src/main/res/layout-v11/install_confirm.xml
@@ -41,7 +41,7 @@
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_marginTop="16dp"
-        android:background="?android:attr/dividerHorizontal"
+        android:background="?attr/dividerHorizontal"
         android:visibility="gone" />
 
     <FrameLayout
@@ -102,7 +102,7 @@
     <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:divider="?android:attr/dividerHorizontal"
+        android:divider="?attr/dividerHorizontal"
         android:orientation="vertical"
         android:showDividers="beginning">
 
diff --git a/app/src/main/res/layout-v17/app_permission_item_money.xml b/app/src/main/res/layout-v17/app_permission_item_money.xml
index 0cca5170d..46ae16c39 100644
--- a/app/src/main/res/layout-v17/app_permission_item_money.xml
+++ b/app/src/main/res/layout-v17/app_permission_item_money.xml
@@ -18,13 +18,14 @@
   Defines the layout of a single permission item that costs money.
 -->
 
-<view class="org.fdroid.fdroid.privileged.views.AppSecurityPermissions$PermissionItemView"
+<view
+    class="org.fdroid.fdroid.privileged.views.AppSecurityPermissions$PermissionItemView"
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:orientation="horizontal"
-    android:background="?android:attr/selectableItemBackground">
+    android:background="?attr/selectableItemBackground">
 
     <ImageView
         android:id="@+id/perm_icon"
@@ -37,7 +38,7 @@
     <ImageView
         android:layout_width="wrap_content"
         android:layout_height="match_parent"
-        android:background="?android:attr/dividerVertical" />
+        android:background="?attr/dividerVertical" />
 
     <RelativeLayout
         android:layout_width="match_parent"
@@ -61,7 +62,7 @@
             android:scaleType="fitCenter"
             app:tint="@color/perms_costs_money"
             android:tintMode="src_in"
-            android:src="@drawable/ic_coins_s" />
+            app:srcCompat="@drawable/ic_coins_s" />
         <TextView
             android:id="@+id/perm_money_label"
             android:textAppearance="?android:attr/textAppearanceSmall"
diff --git a/app/src/main/res/layout/activity_app_list.xml b/app/src/main/res/layout/activity_app_list.xml
index 3484e90d3..858fbf50f 100644
--- a/app/src/main/res/layout/activity_app_list.xml
+++ b/app/src/main/res/layout/activity_app_list.xml
@@ -34,7 +34,7 @@
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:contentDescription="@string/back"
-                android:src="@drawable/ic_back"
+                app:srcCompat="@drawable/ic_back"
                 app:layout_constraintBottom_toBottomOf="parent"
                 app:layout_constraintStart_toStartOf="parent"
                 app:layout_constraintTop_toTopOf="parent"/>
@@ -60,7 +60,7 @@
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:contentDescription="@string/clear_search"
-                android:src="@drawable/ic_clear"
+                app:srcCompat="@drawable/ic_clear"
                 app:layout_constraintBottom_toBottomOf="parent"
                 app:layout_constraintEnd_toEndOf="parent"
                 app:layout_constraintTop_toTopOf="parent"/>
diff --git a/app/src/main/res/layout/activity_repo_details.xml b/app/src/main/res/layout/activity_repo_details.xml
index f155f236a..61b3f336b 100644
--- a/app/src/main/res/layout/activity_repo_details.xml
+++ b/app/src/main/res/layout/activity_repo_details.xml
@@ -145,7 +145,7 @@
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
                 android:paddingTop="16dp"
-                android:src="@drawable/swap_qr_example" />
+                app:srcCompat="@drawable/swap_qr_example" />
 
         </LinearLayout>
 
diff --git a/app/src/main/res/layout/app_details2_header.xml b/app/src/main/res/layout/app_details2_header.xml
index ea6441021..8e1e85ca8 100644
--- a/app/src/main/res/layout/app_details2_header.xml
+++ b/app/src/main/res/layout/app_details2_header.xml
@@ -42,7 +42,7 @@
                     android:layout_marginEnd="8dp"
                     android:layout_marginRight="8dp"
                     android:scaleType="fitCenter"
-                    android:src="@drawable/ic_repo_app_default"
+                    app:srcCompat="@drawable/ic_repo_app_default"
                     android:transitionName="@string/transition_app_item_icon" />
 
                 <!-- Name, Author (optional), Updated date -->
@@ -97,7 +97,7 @@
                     android:layout_alignParentRight="true"
                     android:layout_centerVertical="true"
                     android:contentDescription="@string/app__tts__cancel_download"
-                    android:src="@android:drawable/ic_menu_close_clear_cancel" />
+                    app:srcCompat="@android:drawable/ic_menu_close_clear_cancel" />
 
                 <TextView
                     android:id="@+id/progress_label"
diff --git a/app/src/main/res/layout/app_details2_version_item.xml b/app/src/main/res/layout/app_details2_version_item.xml
index 6c5619096..807b25da1 100644
--- a/app/src/main/res/layout/app_details2_version_item.xml
+++ b/app/src/main/res/layout/app_details2_version_item.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<RelativeLayout
+<RelativeLayout xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:orientation="vertical"
@@ -84,7 +84,7 @@
         <ImageView android:id="@+id/expand_arrow"
             android:layout_width="wrap_content"
             android:layout_height="match_parent"
-            android:src="@drawable/ic_expand_more" />
+            app:srcCompat="@drawable/ic_expand_more" />
     </LinearLayout>
 
     <LinearLayout android:id="@+id/expanded_layout"
diff --git a/app/src/main/res/layout/donate_bitcoin.xml b/app/src/main/res/layout/donate_bitcoin.xml
index 3730e1c38..18115496c 100644
--- a/app/src/main/res/layout/donate_bitcoin.xml
+++ b/app/src/main/res/layout/donate_bitcoin.xml
@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <ImageView
     xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="80dp"
     android:layout_height="30dp"
     android:padding="4dp"
@@ -8,5 +9,5 @@
     android:layout_marginLeft="4dp"
     android:layout_marginEnd="4dp"
     android:layout_marginRight="4dp"
-    android:src="@drawable/donation_option_bitcoin"
+    app:srcCompat="@drawable/donation_option_bitcoin"
     android:contentDescription="@string/menu_bitcoin" />
\ No newline at end of file
diff --git a/app/src/main/res/layout/donate_liberapay.xml b/app/src/main/res/layout/donate_liberapay.xml
index f08246385..cb75a2501 100644
--- a/app/src/main/res/layout/donate_liberapay.xml
+++ b/app/src/main/res/layout/donate_liberapay.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <ImageView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="80dp"
     android:layout_height="28dp"
     android:layout_marginEnd="12dp"
@@ -7,4 +8,4 @@
     android:layout_marginRight="12dp"
     android:layout_marginStart="12dp"
     android:contentDescription="@string/menu_liberapay"
-    android:src="@drawable/donation_option_liberapay" />
\ No newline at end of file
+    app:srcCompat="@drawable/donation_option_liberapay" />
\ No newline at end of file
diff --git a/app/src/main/res/layout/donate_litecoin.xml b/app/src/main/res/layout/donate_litecoin.xml
index 297a40c6b..dbd5560e2 100644
--- a/app/src/main/res/layout/donate_litecoin.xml
+++ b/app/src/main/res/layout/donate_litecoin.xml
@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <ImageView
     xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="80dp"
     android:layout_height="30dp"
     android:padding="2dp"
@@ -8,5 +9,5 @@
     android:layout_marginLeft="4dp"
     android:layout_marginEnd="4dp"
     android:layout_marginRight="4dp"
-    android:src="@drawable/donation_option_litecoin"
+    app:srcCompat="@drawable/donation_option_litecoin"
     android:contentDescription="@string/menu_litecoin" />
\ No newline at end of file
diff --git a/app/src/main/res/layout/donate_opencollective.xml b/app/src/main/res/layout/donate_opencollective.xml
index 65f519f8f..0099f5ced 100644
--- a/app/src/main/res/layout/donate_opencollective.xml
+++ b/app/src/main/res/layout/donate_opencollective.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <ImageView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="80dp"
     android:layout_height="28dp"
     android:layout_marginEnd="12dp"
@@ -7,4 +8,4 @@
     android:layout_marginRight="12dp"
     android:layout_marginStart="12dp"
     android:contentDescription="@string/menu_opencollective"
-    android:src="@drawable/donation_option_opencollective" />
\ No newline at end of file
+    app:srcCompat="@drawable/donation_option_opencollective" />
\ No newline at end of file
diff --git a/app/src/main/res/layout/fab_search.xml b/app/src/main/res/layout/fab_search.xml
index e7ea646fd..8838df345 100644
--- a/app/src/main/res/layout/fab_search.xml
+++ b/app/src/main/res/layout/fab_search.xml
@@ -1,8 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
 <com.google.android.material.floatingactionbutton.FloatingActionButton
     xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:id="@+id/fab_search"
-    android:src="@drawable/ic_search"
+    app:srcCompat="@drawable/ic_search"
     android:contentDescription="@string/menu_search"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
diff --git a/app/src/main/res/layout/install_confirm.xml b/app/src/main/res/layout/install_confirm.xml
index d4d4f8866..d3a621034 100644
--- a/app/src/main/res/layout/install_confirm.xml
+++ b/app/src/main/res/layout/install_confirm.xml
@@ -100,7 +100,7 @@
     <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:divider="?android:attr/dividerHorizontal"
+        android:divider="?attr/dividerHorizontal"
         android:orientation="vertical"
         android:showDividers="beginning">
 
diff --git a/app/src/main/res/layout/known_vuln_app_list_item.xml b/app/src/main/res/layout/known_vuln_app_list_item.xml
index a1c4ead43..138813a80 100644
--- a/app/src/main/res/layout/known_vuln_app_list_item.xml
+++ b/app/src/main/res/layout/known_vuln_app_list_item.xml
@@ -31,7 +31,7 @@
         android:layout_marginStart="48dp"
         android:layout_marginLeft="48dp"
         android:layout_marginTop="40dp"
-        android:src="@drawable/ic_known_vuln_overlay"
+        app:srcCompat="@drawable/ic_known_vuln_overlay"
         android:scaleType="fitCenter"
         tools:ignore="ContentDescription"/>
 
diff --git a/app/src/main/res/layout/main_tab_updates.xml b/app/src/main/res/layout/main_tab_updates.xml
index f27373dec..66e0e4bc2 100644
--- a/app/src/main/res/layout/main_tab_updates.xml
+++ b/app/src/main/res/layout/main_tab_updates.xml
@@ -49,7 +49,7 @@
                 android:id="@+id/image"
                 android:layout_width="0dp"
                 android:layout_height="0dp"
-                android:src="@drawable/no_updates_bg"
+                app:srcCompat="@drawable/no_updates_bg"
                 android:importantForAccessibility="no"
                 app:layout_constraintRight_toRightOf="parent"
                 app:layout_constraintLeft_toLeftOf="parent"
diff --git a/app/src/main/res/layout/preference_seekbar.xml b/app/src/main/res/layout/preference_seekbar.xml
index 7b19aa539..325e82038 100644
--- a/app/src/main/res/layout/preference_seekbar.xml
+++ b/app/src/main/res/layout/preference_seekbar.xml
@@ -6,7 +6,7 @@
                 android:layout_marginStart="16dip"
                 android:layout_marginEnd="16dip">
 
-    <TextView android:id="@+android:id/title"
+        <TextView android:id="@android:id/title"
               android:layout_width="match_parent"
               android:layout_height="wrap_content"
               android:singleLine="true"
@@ -15,7 +15,7 @@
               android:ellipsize="marquee"
               android:fadingEdge="horizontal"/>
 
-    <TextView android:id="@+android:id/summary"
+        <TextView android:id="@android:id/summary"
               android:layout_width="match_parent"
               android:layout_height="wrap_content"
               android:layout_below="@android:id/title"
diff --git a/app/src/main/res/layout/repo_item.xml b/app/src/main/res/layout/repo_item.xml
index d2c3a1711..413558fcf 100644
--- a/app/src/main/res/layout/repo_item.xml
+++ b/app/src/main/res/layout/repo_item.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
-    android:layout_height="?android:attr/listPreferredItemHeight"
+    android:layout_height="?attr/listPreferredItemHeight"
     android:orientation="horizontal"
     android:gravity="center_vertical"
     android:paddingLeft="?attr/listPreferredItemPaddingLeft"
diff --git a/app/src/main/res/layout/share_header_item.xml b/app/src/main/res/layout/share_header_item.xml
index 809d4f9f4..7617d860c 100644
--- a/app/src/main/res/layout/share_header_item.xml
+++ b/app/src/main/res/layout/share_header_item.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:orientation="vertical"
@@ -17,7 +18,7 @@
         android:layout_alignParentTop="true"
         android:scaleType="centerCrop"
         android:layout_gravity="center_horizontal"
-        android:src="@drawable/ic_nearby_share"
+        app:srcCompat="@drawable/ic_nearby_share"
         android:layout_marginRight="10dp"
         android:layout_marginEnd="10dp"
         />
diff --git a/app/src/main/res/layout/updateable_app_status_item.xml b/app/src/main/res/layout/updateable_app_status_item.xml
index 5860080e7..a185ae0e7 100644
--- a/app/src/main/res/layout/updateable_app_status_item.xml
+++ b/app/src/main/res/layout/updateable_app_status_item.xml
@@ -79,7 +79,7 @@
             android:paddingRight="8dp"
             android:paddingStart="8dp"
             android:paddingEnd="8dp"
-            android:src="@drawable/ic_cancel"
+            app:srcCompat="@drawable/ic_cancel"
             android:contentDescription="@string/cancel"
             android:background="@android:color/transparent"
             android:visibility="gone"
diff --git a/app/src/main/res/values-v16/styles.xml b/app/src/main/res/values-v16/styles.xml
index 8ed5bae82..ebbe249c9 100644
--- a/app/src/main/res/values-v16/styles.xml
+++ b/app/src/main/res/values-v16/styles.xml
@@ -7,6 +7,6 @@
     <style name="BodyText" parent="BodyTextV16"/>
 
     <style name="AppListItemStatusText" parent="AppListItemStatusTextBase">
-        <item name="android:fontFamily">sans-serif-light</item>
+        <item name="fontFamily">sans-serif-light</item>
     </style>
 </resources>
diff --git a/app/src/main/res/values-v17/styles_detail.xml b/app/src/main/res/values-v17/styles_detail.xml
index a9c311d27..9f1d06a40 100644
--- a/app/src/main/res/values-v17/styles_detail.xml
+++ b/app/src/main/res/values-v17/styles_detail.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
     <style name="DetailsButtonStyle" parent="DetailsButtonStyleBase">
-        <item name="android:paddingStart">20dp</item>
-        <item name="android:paddingEnd">20dp</item>
+        <item name="paddingStart">20dp</item>
+        <item name="paddingEnd">20dp</item>
     </style>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values-v21/styles.xml b/app/src/main/res/values-v21/styles.xml
index e96130540..043fee11d 100644
--- a/app/src/main/res/values-v21/styles.xml
+++ b/app/src/main/res/values-v21/styles.xml
@@ -3,8 +3,8 @@
 
     <style name="AppThemeDark" parent="AppBaseThemeDark">
         <!-- customizations that are not API-level specific go here. -->
-        <item name="android:alertDialogTheme">@style/AlertDialogThemeDark</item>
-        <item name="android:actionOverflowButtonStyle">@style/ActionButtonOverflow</item>
+        <item name="alertDialogTheme">@style/AlertDialogThemeDark</item>
+        <item name="actionOverflowButtonStyle">@style/ActionButtonOverflow</item>
         <item name="android:navigationBarColor">@android:color/black</item>
         <item name="android:windowSharedElementEnterTransition">@transition/shared_elements</item>
         <item name="android:windowSharedElementExitTransition">@transition/shared_elements</item>
@@ -12,9 +12,9 @@
 
     <style name="AppThemeLight" parent="AppBaseThemeLight">
         <!-- customizations that are not API-level specific go here. -->
-        <item name="android:alertDialogTheme">@style/AlertDialogThemeLight</item>
+        <item name="alertDialogTheme">@style/AlertDialogThemeLight</item>
         <item name="android:colorEdgeEffect">@color/fdroid_blue</item>
-        <item name="android:actionOverflowButtonStyle">@style/ActionButtonOverflow</item>
+        <item name="actionOverflowButtonStyle">@style/ActionButtonOverflow</item>
         <item name="android:windowSharedElementEnterTransition">@transition/shared_elements</item>
         <item name="android:windowSharedElementExitTransition">@transition/shared_elements</item>
     </style>
diff --git a/app/src/main/res/values-v23/styles.xml b/app/src/main/res/values-v23/styles.xml
index 4e2777222..505b074b8 100644
--- a/app/src/main/res/values-v23/styles.xml
+++ b/app/src/main/res/values-v23/styles.xml
@@ -3,7 +3,7 @@
 
     <style name="AppThemeNight" parent="AppBaseThemeNight">
         <!-- set all card views a bit darker than default dark theme -->
-        <item name="android:colorBackgroundFloating">@color/fdroid_night</item>
+        <item name="colorBackgroundFloating">@color/fdroid_night</item>
         <item name="appDetailsCardBackground">@color/fdroid_night</item>
     </style>
 
diff --git a/app/src/main/res/values/styles_detail.xml b/app/src/main/res/values/styles_detail.xml
index b202e7f51..04bf4dc9b 100644
--- a/app/src/main/res/values/styles_detail.xml
+++ b/app/src/main/res/values/styles_detail.xml
@@ -9,14 +9,14 @@
         <item name="android:paddingBottom">10dp</item>
         <item name="android:paddingLeft">18dp</item>
         <item name="android:paddingRight">18dp</item>
-        <item name="android:textAllCaps">true</item>
+        <item name="textAllCaps">true</item>
     </style>
 
     <style name="DetailsButtonStyle" parent="DetailsButtonStyleBase"/>
 
     <style name="DetailsPrimaryButtonStyle" parent="DetailsButtonStyle">
         <item name="android:textColor">#ffffff</item>
-        <item name="android:background">@drawable/button_primary_background_selector</item>
+        <item name="background">@drawable/button_primary_background_selector</item>
     </style>
 
     <style name="DetailsPrimaryButtonStyleSmall" parent="DetailsPrimaryButtonStyle">
@@ -29,7 +29,7 @@
 
     <style name="DetailsSecondaryButtonStyle" parent="DetailsButtonStyle">
         <item name="android:textColor">@color/fdroid_blue</item>
-        <item name="android:background">@drawable/button_secondary_background_selector</item>
+        <item name="background">@drawable/button_secondary_background_selector</item>
     </style>
 
     <style name="DetailsSecondaryButtonStyleSmall" parent="DetailsSecondaryButtonStyle">
@@ -45,7 +45,7 @@
         <item name="android:textSize">14sp</item>
         <item name="android:textStyle">normal</item>
         <item name="android:textColor">@color/fdroid_blue</item>
-        <item name="android:background">?attr/selectableItemBackground</item>
+        <item name="background">?attr/selectableItemBackground</item>
     </style>
 
     <style name="DetailsAppTitleStyle" parent="TextAppearance.AppCompat.Title">
diff --git a/gradle/verification-metadata.xml b/gradle/verification-metadata.xml
index 5ce758fee..ed52efdf1 100644
--- a/gradle/verification-metadata.xml
+++ b/gradle/verification-metadata.xml
@@ -1360,6 +1360,12 @@
             <sha256 value="d3610165c6de2b4d8d6418487717b63c52b5a39c5e35a553e24873ecb60e0628" origin="Generated by Gradle"/>
          </artifact>
       </component>
+      <component group="com.google.guava" name="listenablefuture" version="1.0">
+         <artifact name="listenablefuture-1.0.jar">
+            <pgp value="bdb5fa4fe719d787fb3d3197f6d4a1d411e9d1ae"/>
+            <sha256 value="e4ad7607e5c0477c6f890ef26a49cb8d1bb4dffb650bab4502afee64644e3069" origin="Generated by Gradle"/>
+         </artifact>
+      </component>
       <component group="com.google.guava" name="listenablefuture" version="9999.0-empty-to-avoid-conflict-with-guava">
          <artifact name="listenablefuture-9999.0-empty-to-avoid-conflict-with-guava.jar">
             <sha256 value="b372a037d4230aa57fbeffdef30fd6123f9c0c2db85d0aced00c91b974f33f99" origin="Generated by Gradle"/>
@@ -1749,6 +1755,7 @@
       <component group="junit" name="junit" version="4.13.1">
          <artifact name="junit-4.13.1.jar">
             <pgp value="ff6e2c001948c5f2f38b0cc385911f425ec61b51"/>
+            <sha256 value="c30719db974d6452793fe191b3638a5777005485bae145924044530ffa5f6122" origin="Generated by Gradle"/>
          </artifact>
       </component>
       <component group="nekohtml" name="nekohtml" version="1.9.6.2">
@@ -2506,6 +2513,16 @@
             <sha256 value="daa4f98393b7196473ac7b347618a244d3c7eaa3554b5f86f9cddcce6a4cded6" origin="Generated by Gradle"/>
          </artifact>
       </component>
+      <component group="org.jetbrains.kotlinx" name="kotlinx-coroutines-android" version="1.3.4">
+         <artifact name="kotlinx-coroutines-android-1.3.4.jar">
+            <sha256 value="f36ea75c31934bfad0682cfc435cce922e28b3bffa5af26cf86f07db13008f8a" origin="Generated by Gradle"/>
+         </artifact>
+      </component>
+      <component group="org.jetbrains.kotlinx" name="kotlinx-coroutines-core" version="1.3.4">
+         <artifact name="kotlinx-coroutines-core-1.3.4.jar">
+            <sha256 value="17bec6112d93f5fcb11c27ecc8a14b48e30a5689ccf42c95025b89ba2210c28f" origin="Generated by Gradle"/>
+         </artifact>
+      </component>
       <component group="org.jetbrains.trove4j" name="trove4j" version="20160824">
          <artifact name="trove4j-20160824.jar">
             <sha256 value="1917871c8deb468307a584680c87a44572f5a8b0b98c6d397fc0f5f86596dbe7" origin="Generated by Gradle because artifact wasn't signed">
@@ -2534,6 +2551,11 @@
             <sha256 value="0a84c20cf71f6a3d21fe226b0d588332fc7ae3e90cb583c60a483317eb9f3644" origin="Generated by Gradle"/>
          </artifact>
       </component>
+      <component group="org.mockito" name="mockito-core" version="2.19.0">
+         <artifact name="mockito-core-2.19.0.jar">
+            <sha256 value="d6ac2e04164c5d5c89e73838dc1c8b3856ca6582d3f2daf91816fd9d7ba3c9a9" origin="Generated by Gradle"/>
+         </artifact>
+      </component>
       <component group="org.mockito" name="mockito-core" version="3.3.3">
          <artifact name="mockito-core-3.3.3.jar">
             <pgp value="cc4483cd6a3eb2939b948667a1b4460d8ba7b9af"/>