diff --git a/src/org/fdroid/fdroid/data/ApkProvider.java b/src/org/fdroid/fdroid/data/ApkProvider.java
index b957b2093..6c9afbdeb 100644
--- a/src/org/fdroid/fdroid/data/ApkProvider.java
+++ b/src/org/fdroid/fdroid/data/ApkProvider.java
@@ -64,7 +64,7 @@ public class ApkProvider extends FDroidProvider {
             return cursorToList(cursor);
         }
 
-        private static List<Apk> cursorToList(Cursor cursor) {
+        public static List<Apk> cursorToList(Cursor cursor) {
             List<Apk> apks = new ArrayList<Apk>();
             if (cursor != null) {
                 cursor.moveToFirst();
@@ -77,20 +77,16 @@ public class ApkProvider extends FDroidProvider {
             return apks;
         }
 
-        public static void deleteApksByRepo(Context context, Repo repo) {
+        public static int deleteApksByRepo(Context context, Repo repo) {
             ContentResolver resolver = context.getContentResolver();
-            Uri uri = getContentUri();
-            String[] args = { Long.toString(repo.getId()) };
-            String selection = DataColumns.REPO_ID + " = ?";
-            int count = resolver.delete(uri, selection, args);
+            Uri uri = getRepoUri(repo.getId());
+            return resolver.delete(uri, null, null);
         }
 
         public static void deleteApksByApp(Context context, App app) {
             ContentResolver resolver = context.getContentResolver();
-            Uri uri = getContentUri();
-            String[] args = { app.id };
-            String selection = DataColumns.APK_ID + " = ?";
-            resolver.delete(uri, selection, args);
+            Uri uri = getAppUri(app.id);
+            resolver.delete(uri, null, null);
         }
 
         public static Apk find(Context context, String id, int versionCode) {
@@ -340,7 +336,7 @@ public class ApkProvider extends FDroidProvider {
     }
 
     private QuerySelection queryApp(String appId) {
-        String selection = " id = ? ";
+        String selection = DataColumns.APK_ID + " = ? ";
         String[] args = new String[] { appId };
         return new QuerySelection(selection, args);
     }
@@ -357,7 +353,7 @@ public class ApkProvider extends FDroidProvider {
     }
 
     private QuerySelection queryRepo(long repoId) {
-        String selection = " repo = ? ";
+        String selection = DataColumns.REPO_ID + " = ? ";
         String[] args = new String[]{ Long.toString(repoId) };
         return new QuerySelection(selection, args);
     }
@@ -442,6 +438,7 @@ public class ApkProvider extends FDroidProvider {
     @Override
     public Uri insert(Uri uri, ContentValues values) {
         removeRepoFields(values);
+        validateFields(DataColumns.ALL, values);
         long id = write().insertOrThrow(getTableName(), null, values);
         if (!isApplyingBatch()) {
             getContext().getContentResolver().notifyChange(uri, null);
@@ -458,18 +455,30 @@ public class ApkProvider extends FDroidProvider {
         QuerySelection query = new QuerySelection(where, whereArgs);
 
         switch (matcher.match(uri)) {
-            case CODE_LIST:
-                // Don't support deleting of multiple apks yet.
-                return 0;
 
             case CODE_REPO:
                 query = query.add(queryRepo(Long.parseLong(uri.getLastPathSegment())));
                 break;
 
-            case CODE_SINGLE:
-                query = query.add(querySingle(uri));
+            case CODE_APP:
+                query = query.add(queryApp(uri.getLastPathSegment()));
                 break;
 
+            case CODE_LIST:
+                throw new UnsupportedOperationException(
+                    "Can't delete all apks. " +
+                    "Can only delete those belonging to an app, or a repo.");
+
+            case CODE_APKS:
+                throw new UnsupportedOperationException(
+                    "Can't delete arbitrary apks. " +
+                    "Can only delete those belonging to an app, or a repo.");
+
+            case CODE_SINGLE:
+                throw new UnsupportedOperationException(
+                    "Can't delete individual apks. " +
+                    "Can only delete those belonging to an app, or a repo.");
+
             default:
                 Log.e("FDroid", "Invalid URI for apk content provider: " + uri);
                 throw new UnsupportedOperationException("Invalid URI for apk content provider: " + uri);
@@ -486,6 +495,8 @@ public class ApkProvider extends FDroidProvider {
 
         QuerySelection query = new QuerySelection(where, whereArgs);
 
+        validateFields(DataColumns.ALL, values);
+
         switch (matcher.match(uri)) {
             case CODE_LIST:
                 return 0;
diff --git a/src/org/fdroid/fdroid/data/FDroidProvider.java b/src/org/fdroid/fdroid/data/FDroidProvider.java
index 3e0c4b316..e056eef3e 100644
--- a/src/org/fdroid/fdroid/data/FDroidProvider.java
+++ b/src/org/fdroid/fdroid/data/FDroidProvider.java
@@ -1,5 +1,6 @@
 package org.fdroid.fdroid.data;
 
+import android.annotation.TargetApi;
 import android.content.*;
 import android.database.sqlite.SQLiteDatabase;
 import android.net.Uri;
@@ -95,5 +96,24 @@ public abstract class FDroidProvider extends ContentProvider {
         }
         return sb.toString();
     }
+
+    @TargetApi(11)
+    protected void validateFields(String[] validFields, ContentValues values)
+        throws IllegalArgumentException {
+        for (String key : values.keySet()) {
+            boolean isValid = false;
+            for (String validKey : validFields) {
+                if (validKey.equals(key)) {
+                    isValid = true;
+                    break;
+                }
+            }
+
+            if (!isValid) {
+                throw new IllegalArgumentException(
+                    "Cannot save field '" + key + "' to provider " + getProviderName());
+            }
+        }
+    }
 }
 
diff --git a/src/org/fdroid/fdroid/data/Repo.java b/src/org/fdroid/fdroid/data/Repo.java
index d5bc3bc56..1b0bdd055 100644
--- a/src/org/fdroid/fdroid/data/Repo.java
+++ b/src/org/fdroid/fdroid/data/Repo.java
@@ -14,7 +14,7 @@ public class Repo extends ValueObject {
 
     public static final int VERSION_DENSITY_SPECIFIC_ICONS = 11;
 
-    private long id;
+    protected long id;
 
     public String address;
     public String name;
diff --git a/test/src/org/fdroid/fdroid/ApkProviderTest.java b/test/src/org/fdroid/fdroid/ApkProviderTest.java
index 795172d27..0785a87db 100644
--- a/test/src/org/fdroid/fdroid/ApkProviderTest.java
+++ b/test/src/org/fdroid/fdroid/ApkProviderTest.java
@@ -2,10 +2,14 @@ package org.fdroid.fdroid;
 
 import android.content.ContentValues;
 import android.database.Cursor;
+import android.net.Uri;
 import org.fdroid.fdroid.data.Apk;
 import org.fdroid.fdroid.data.ApkProvider;
 import org.fdroid.fdroid.data.AppProvider;
+import org.fdroid.fdroid.data.RepoProvider;
 import org.fdroid.fdroid.mock.MockApk;
+import org.fdroid.fdroid.mock.MockApp;
+import org.fdroid.fdroid.mock.MockRepo;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -20,13 +24,14 @@ public class ApkProviderTest extends FDroidProviderTest<ApkProvider> {
         return new String[] {
             ApkProvider.DataColumns.APK_ID,
             ApkProvider.DataColumns.VERSION_CODE,
-            ApkProvider.DataColumns.NAME
+            ApkProvider.DataColumns.NAME,
+            ApkProvider.DataColumns.REPO_ID
         };
     }
 
     public void testUris() {
         assertInvalidUri(ApkProvider.getAuthority());
-        assertInvalidUri(AppProvider.getContentUri());
+        assertInvalidUri(RepoProvider.getContentUri());
 
         List<Apk> apks = new ArrayList<Apk>(3);
         for (int i = 0; i < 10; i ++) {
@@ -61,7 +66,86 @@ public class ApkProviderTest extends FDroidProviderTest<ApkProvider> {
         } catch (Exception e) {
             fail();
         }
+    }
 
+    public void testAppApks() {
+        for (int i = 1; i <= 10; i ++) {
+            insertApk("org.fdroid.fdroid", i);
+            insertApk("com.example", i);
+        }
+
+        assertTotalApkCount(20);
+
+        Cursor fdroidApks = getMockContentResolver().query(
+                ApkProvider.getAppUri("org.fdroid.fdroid"),
+                getMinimalProjection(),
+                null, null, null);
+        assertResultCount(10, fdroidApks);
+        assertBelongsToApp(fdroidApks, "org.fdroid.fdroid");
+
+        Cursor exampleApks = getMockContentResolver().query(
+                ApkProvider.getAppUri("com.example"),
+                getMinimalProjection(),
+                null, null, null);
+        assertResultCount(10, exampleApks);
+        assertBelongsToApp(exampleApks, "com.example");
+
+        ApkProvider.Helper.deleteApksByApp(getMockContext(), new MockApp("com.example"));
+
+        Cursor all = queryAllApks();
+        assertResultCount(10, all);
+        assertBelongsToApp(all, "org.fdroid.fdroid");
+    }
+
+    public void testInvalidDeleteUris() {
+        assertCantDelete(ApkProvider.getContentUri());
+        assertCantDelete(ApkProvider.getContentUri(new ArrayList<Apk>()));
+        assertCantDelete(ApkProvider.getContentUri("org.fdroid.fdroid", 10));
+        assertCantDelete(ApkProvider.getContentUri(new MockApk("org.fdroid.fdroid", 10)));
+
+        try {
+            getMockContentResolver().delete(RepoProvider.getContentUri(), null, null);
+            fail();
+        } catch (IllegalArgumentException e) {
+            // Don't fail, it is what we were looking for...
+        } catch (Exception e) {
+            fail();
+        }
+    }
+
+    public void testRepoApks() {
+
+        final long REPO_KEEP = 1;
+        final long REPO_DELETE = 2;
+
+        // Insert apks into two repos, one of which we will later purge the
+        // the apks from.
+        for (int i = 1; i <= 5; i ++) {
+            insertApkForRepo("org.fdroid.fdroid", i, REPO_KEEP);
+            insertApkForRepo("com.example." + i, 1, REPO_DELETE);
+        }
+        for (int i = 6; i <= 10; i ++) {
+            insertApkForRepo("org.fdroid.fdroid", i, REPO_DELETE);
+            insertApkForRepo("com.example." + i, 1, REPO_KEEP);
+        }
+
+        assertTotalApkCount(20);
+
+        Cursor cursor = getMockContentResolver().query(
+            ApkProvider.getRepoUri(REPO_DELETE), getMinimalProjection(), null, null, null);
+        assertResultCount(10, cursor);
+        assertBelongsToRepo(cursor, REPO_DELETE);
+
+        int count = ApkProvider.Helper.deleteApksByRepo(getMockContext(), new MockRepo(REPO_DELETE));
+        assertEquals(10, count);
+
+        assertTotalApkCount(10);
+        cursor = getMockContentResolver().query(
+            ApkProvider.getRepoUri(REPO_DELETE), getMinimalProjection(), null, null, null);
+        assertResultCount(0, cursor);
+
+        // The only remaining apks should be those from REPO_KEEP.
+        assertBelongsToRepo(queryAllApks(), REPO_KEEP);
     }
 
     public void testQuery() {
@@ -69,12 +153,6 @@ public class ApkProviderTest extends FDroidProviderTest<ApkProvider> {
         assertNotNull(cursor);
     }
 
-    private void insertApks(int count) {
-        for (int i = 0; i < count; i ++) {
-            insertApk("com.example.test." + i, i);
-        }
-    }
-
     public void testInsert() {
 
         // Start with an empty database...
@@ -82,8 +160,11 @@ public class ApkProviderTest extends FDroidProviderTest<ApkProvider> {
         assertNotNull(cursor);
         assertEquals(0, cursor.getCount());
 
+        Apk apk = new MockApk("org.fdroid.fdroid", 13);
+
         // Insert a new record...
-        insertApk("org.fdroid.fdroid", 13);
+        Uri newUri = insertApk(apk.id, apk.vercode);
+        assertEquals(ApkProvider.getContentUri(apk).toString(), newUri.toString());
         cursor = queryAllApks();
         assertNotNull(cursor);
         assertEquals(1, cursor.getCount());
@@ -103,29 +184,79 @@ public class ApkProviderTest extends FDroidProviderTest<ApkProvider> {
         // value object (because the queryAllApks() helper asks for VERSION_CODE and
         // APK_ID.
         cursor.moveToFirst();
-        Apk apk = new Apk(cursor);
-        assertEquals("org.fdroid.fdroid", apk.id);
-        assertEquals(13, apk.vercode);
+        Apk toCheck = new Apk(cursor);
+        assertEquals("org.fdroid.fdroid", toCheck.id);
+        assertEquals(13, toCheck.vercode);
+    }
+
+    public void testInsertWithExtraFields() {
+
+        assertResultCount(0, queryAllApks());
+
+        String[] repoFields = new String[] {
+            RepoProvider.DataColumns.DESCRIPTION,
+            RepoProvider.DataColumns.ADDRESS,
+            RepoProvider.DataColumns.FINGERPRINT,
+            RepoProvider.DataColumns.NAME,
+            RepoProvider.DataColumns.PUBLIC_KEY
+        };
+
+        for (String field : repoFields) {
+            ContentValues invalidRepo = new ContentValues();
+            invalidRepo.put(field, "Test data");
+            try {
+                insertApk("org.fdroid.fdroid", 10, invalidRepo);
+                fail();
+            } catch (IllegalArgumentException e) {
+            } catch (Exception e) {
+                fail();
+            }
+            assertResultCount(0, queryAllApks());
+        }
+
+        // ApkProvider.DataColumns.REPO
+
     }
 
     public void testIgnore() {
-        for (int i = 0; i < 10; i ++) {
+        /*for (int i = 0; i < 10; i ++) {
             insertApk("org.fdroid.fdroid", i);
-        }
+        }*/
+    }
 
+    private void assertBelongsToApp(Cursor apks, String appId) {
+        for (Apk apk : ApkProvider.Helper.cursorToList(apks)) {
+            assertEquals(appId, apk.id);
+        }
+    }
+
+    private void assertTotalApkCount(int expected) {
+        assertResultCount(expected, queryAllApks());
+    }
+
+    private void assertBelongsToRepo(Cursor apkCursor, long repoId) {
+        for (Apk apk : ApkProvider.Helper.cursorToList(apkCursor)) {
+            assertEquals(repoId, apk.repo);
+        }
+    }
+
+    private void insertApkForRepo(String id, int versionCode, long repoId) {
+        ContentValues additionalValues = new ContentValues();
+        additionalValues.put(ApkProvider.DataColumns.REPO_ID, repoId);
+        insertApk(id, versionCode, additionalValues);
     }
 
     private Cursor queryAllApks() {
         return getMockContentResolver().query(ApkProvider.getContentUri(), getMinimalProjection(), null, null, null);
     }
 
-    private void insertApk(String id, int versionCode) {
-        insertApk(id, versionCode, new ContentValues());
+    private Uri insertApk(String id, int versionCode) {
+        return insertApk(id, versionCode, new ContentValues());
     }
 
-    private void insertApk(String id, int versionCode,
+    private Uri insertApk(String id, int versionCode,
                            ContentValues additionalValues) {
-        TestUtils.insertApk(getMockContentResolver(), id, versionCode, additionalValues);
+        return TestUtils.insertApk(getMockContentResolver(), id, versionCode, additionalValues);
     }
 
 }
diff --git a/test/src/org/fdroid/fdroid/FDroidProviderTest.java b/test/src/org/fdroid/fdroid/FDroidProviderTest.java
index fe85ea6d2..1fe2e3c48 100644
--- a/test/src/org/fdroid/fdroid/FDroidProviderTest.java
+++ b/test/src/org/fdroid/fdroid/FDroidProviderTest.java
@@ -50,6 +50,16 @@ public abstract class FDroidProviderTest<T extends FDroidProvider> extends Provi
         return swappableContext;
     }
 
+    protected void assertCantDelete(Uri uri) {
+        try {
+            getMockContentResolver().delete(uri, null, null);
+            fail();
+        } catch (UnsupportedOperationException e) {
+        } catch (Exception e) {
+            fail();
+        }
+    }
+
     protected void assertInvalidUri(String uri) {
         assertInvalidUri(Uri.parse(uri));
     }
@@ -83,7 +93,11 @@ public abstract class FDroidProviderTest<T extends FDroidProvider> extends Provi
 
     protected void assertResultCount(int expectedCount, Uri uri) {
         Cursor cursor = getMockContentResolver().query(uri, getMinimalProjection(), null, null, null);
-        assertNotNull(cursor);
-        assertEquals(expectedCount, cursor.getCount());
+        assertResultCount(expectedCount, cursor);
+    }
+
+    protected void assertResultCount(int expectedCount, Cursor result) {
+        assertNotNull(result);
+        assertEquals(expectedCount, result.getCount());
     }
 }
diff --git a/test/src/org/fdroid/fdroid/TestUtils.java b/test/src/org/fdroid/fdroid/TestUtils.java
index 19299e10a..420c32c45 100644
--- a/test/src/org/fdroid/fdroid/TestUtils.java
+++ b/test/src/org/fdroid/fdroid/TestUtils.java
@@ -82,7 +82,7 @@ public class TestUtils {
         resolver.insert(uri, values);
     }
 
-    public static void insertApk(ContentResolver resolver, String id, int versionCode, ContentValues additionalValues) {
+    public static Uri insertApk(ContentResolver resolver, String id, int versionCode, ContentValues additionalValues) {
 
         ContentValues values = new ContentValues();
 
@@ -101,6 +101,6 @@ public class TestUtils {
 
         Uri uri = ApkProvider.getContentUri();
 
-        resolver.insert(uri, values);
+        return resolver.insert(uri, values);
     }
 }
diff --git a/test/src/org/fdroid/fdroid/mock/MockRepo.java b/test/src/org/fdroid/fdroid/mock/MockRepo.java
new file mode 100644
index 000000000..3b3fce976
--- /dev/null
+++ b/test/src/org/fdroid/fdroid/mock/MockRepo.java
@@ -0,0 +1,11 @@
+package org.fdroid.fdroid.mock;
+
+import org.fdroid.fdroid.data.Repo;
+
+public class MockRepo extends Repo {
+
+    public MockRepo(long repoId) {
+        id = repoId;
+    }
+
+}