diff --git a/app/src/androidTest/java/de/danoeh/antennapod/core/service/download/StubDownloader.java b/app/src/androidTest/java/de/danoeh/antennapod/core/service/download/StubDownloader.java
index e7fe079a6..7aac738e7 100644
--- a/app/src/androidTest/java/de/danoeh/antennapod/core/service/download/StubDownloader.java
+++ b/app/src/androidTest/java/de/danoeh/antennapod/core/service/download/StubDownloader.java
@@ -1,8 +1,7 @@
 package de.danoeh.antennapod.core.service.download;
 
 import androidx.annotation.NonNull;
-
-import de.danoeh.antennapod.core.util.Consumer;
+import androidx.core.util.Consumer;
 
 public class StubDownloader extends Downloader {
 
diff --git a/app/src/androidTest/java/de/test/antennapod/service/download/DownloadServiceTest.java b/app/src/androidTest/java/de/test/antennapod/service/download/DownloadServiceTest.java
index 229d4b307..b7f062223 100644
--- a/app/src/androidTest/java/de/test/antennapod/service/download/DownloadServiceTest.java
+++ b/app/src/androidTest/java/de/test/antennapod/service/download/DownloadServiceTest.java
@@ -4,6 +4,7 @@ import android.content.Context;
 import android.content.Intent;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+import androidx.core.util.Consumer;
 import androidx.test.InstrumentationRegistry;
 import androidx.test.runner.AndroidJUnit4;
 
@@ -35,7 +36,6 @@ import de.danoeh.antennapod.core.service.download.StubDownloader;
 import de.danoeh.antennapod.core.storage.DBReader;
 import de.danoeh.antennapod.core.storage.DBWriter;
 import de.danoeh.antennapod.core.storage.DownloadRequester;
-import de.danoeh.antennapod.core.util.Consumer;
 
 import static de.test.antennapod.util.event.DownloadEventListener.withDownloadEventListener;
 import static de.test.antennapod.util.event.FeedItemEventListener.withFeedItemEventListener;
diff --git a/app/src/androidTest/java/de/test/antennapod/storage/DBWriterTest.java b/app/src/androidTest/java/de/test/antennapod/storage/DBWriterTest.java
index 10ca281cb..1fb156760 100644
--- a/app/src/androidTest/java/de/test/antennapod/storage/DBWriterTest.java
+++ b/app/src/androidTest/java/de/test/antennapod/storage/DBWriterTest.java
@@ -6,6 +6,7 @@ import android.database.Cursor;
 import android.preference.PreferenceManager;
 import android.util.Log;
 
+import androidx.core.util.Consumer;
 import androidx.test.InstrumentationRegistry;
 import androidx.test.filters.MediumTest;
 
@@ -31,7 +32,6 @@ import de.danoeh.antennapod.core.preferences.UserPreferences;
 import de.danoeh.antennapod.core.storage.DBReader;
 import de.danoeh.antennapod.core.storage.DBWriter;
 import de.danoeh.antennapod.core.storage.PodDBAdapter;
-import de.danoeh.antennapod.core.util.Consumer;
 import de.danoeh.antennapod.core.util.FeedItemUtil;
 
 import static androidx.test.InstrumentationRegistry.getInstrumentation;
diff --git a/app/src/main/java/de/danoeh/antennapod/activity/MediaplayerActivity.java b/app/src/main/java/de/danoeh/antennapod/activity/MediaplayerActivity.java
index c0ba75ba6..698d7e295 100644
--- a/app/src/main/java/de/danoeh/antennapod/activity/MediaplayerActivity.java
+++ b/app/src/main/java/de/danoeh/antennapod/activity/MediaplayerActivity.java
@@ -22,9 +22,12 @@ import android.widget.Toast;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.AlertDialog;
+import androidx.arch.core.util.Function;
 import androidx.core.app.ActivityCompat;
 import androidx.core.app.ActivityOptionsCompat;
 import androidx.core.content.ContextCompat;
+import androidx.core.util.Consumer;
+import androidx.core.util.Supplier;
 import com.bumptech.glide.Glide;
 import de.danoeh.antennapod.R;
 import de.danoeh.antennapod.core.event.PlaybackPositionEvent;
@@ -35,15 +38,12 @@ import de.danoeh.antennapod.core.preferences.UserPreferences;
 import de.danoeh.antennapod.core.service.playback.PlaybackService;
 import de.danoeh.antennapod.core.storage.DBReader;
 import de.danoeh.antennapod.core.storage.DBWriter;
-import de.danoeh.antennapod.core.util.Consumer;
 import de.danoeh.antennapod.core.util.Converter;
 import de.danoeh.antennapod.core.util.FeedItemUtil;
 import de.danoeh.antennapod.core.util.Flavors;
-import de.danoeh.antennapod.core.util.Function;
 import de.danoeh.antennapod.core.util.IntentUtils;
 import de.danoeh.antennapod.core.util.ShareUtils;
 import de.danoeh.antennapod.core.util.StorageUtils;
-import de.danoeh.antennapod.core.util.Supplier;
 import de.danoeh.antennapod.core.util.TimeSpeedConverter;
 import de.danoeh.antennapod.core.util.gui.PictureInPictureUtil;
 import de.danoeh.antennapod.core.util.playback.ExternalMedia;
diff --git a/app/src/main/java/de/danoeh/antennapod/view/ShownotesWebView.java b/app/src/main/java/de/danoeh/antennapod/view/ShownotesWebView.java
index 3ea57eb5e..88efc1f84 100644
--- a/app/src/main/java/de/danoeh/antennapod/view/ShownotesWebView.java
+++ b/app/src/main/java/de/danoeh/antennapod/view/ShownotesWebView.java
@@ -15,11 +15,9 @@ import android.view.View;
 import android.webkit.WebSettings;
 import android.webkit.WebView;
 import android.webkit.WebViewClient;
-import androidx.core.content.ContextCompat;
+import androidx.core.util.Consumer;
 import com.google.android.material.snackbar.Snackbar;
 import de.danoeh.antennapod.R;
-import de.danoeh.antennapod.core.preferences.UserPreferences;
-import de.danoeh.antennapod.core.util.Consumer;
 import de.danoeh.antennapod.core.util.Converter;
 import de.danoeh.antennapod.core.util.IntentUtils;
 import de.danoeh.antennapod.core.util.NetworkUtils;
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/Consumer.java b/core/src/main/java/de/danoeh/antennapod/core/util/Consumer.java
deleted file mode 100644
index 13a87af0d..000000000
--- a/core/src/main/java/de/danoeh/antennapod/core/util/Consumer.java
+++ /dev/null
@@ -1,5 +0,0 @@
-package de.danoeh.antennapod.core.util;
-
-public interface Consumer<T> {
-    void accept(T t);
-}
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/Function.java b/core/src/main/java/de/danoeh/antennapod/core/util/Function.java
deleted file mode 100644
index c4f4ad68a..000000000
--- a/core/src/main/java/de/danoeh/antennapod/core/util/Function.java
+++ /dev/null
@@ -1,7 +0,0 @@
-package de.danoeh.antennapod.core.util;
-
-import io.reactivex.annotations.NonNull;
-
-public interface Function<T, R> {
-    R apply(@NonNull T t);
-}
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/Supplier.java b/core/src/main/java/de/danoeh/antennapod/core/util/Supplier.java
deleted file mode 100644
index 796b03154..000000000
--- a/core/src/main/java/de/danoeh/antennapod/core/util/Supplier.java
+++ /dev/null
@@ -1,5 +0,0 @@
-package de.danoeh.antennapod.core.util;
-
-public interface Supplier<T> {
-    T get();
-}