diff --git a/app/build.gradle b/app/build.gradle
index 054d91fa5..795f4488f 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -102,7 +102,7 @@ ext {
     checkstyleVersion = '8.38'
 
     androidxLifecycleVersion = '2.2.0'
-    androidxRoomVersion = '2.3.0-alpha03'
+    androidxRoomVersion = '2.3.0'
 
     icepickVersion = '3.2.0'
     exoPlayerVersion = '2.12.3'
diff --git a/app/src/main/java/org/schabi/newpipe/database/Converters.java b/app/src/main/java/org/schabi/newpipe/database/Converters.java
deleted file mode 100644
index c46b5f427..000000000
--- a/app/src/main/java/org/schabi/newpipe/database/Converters.java
+++ /dev/null
@@ -1,64 +0,0 @@
-package org.schabi.newpipe.database;
-
-import androidx.room.TypeConverter;
-
-import org.schabi.newpipe.extractor.stream.StreamType;
-import org.schabi.newpipe.local.subscription.FeedGroupIcon;
-
-import java.time.Instant;
-import java.time.OffsetDateTime;
-import java.time.ZoneOffset;
-
-public final class Converters {
-    private Converters() { }
-
-    /**
-     * Convert a long value to a {@link OffsetDateTime}.
-     *
-     * @param value the long value
-     * @return the {@code OffsetDateTime}
-     */
-    @TypeConverter
-    public static OffsetDateTime offsetDateTimeFromTimestamp(final Long value) {
-        return value == null ? null : OffsetDateTime.ofInstant(Instant.ofEpochMilli(value),
-                ZoneOffset.UTC);
-    }
-
-    /**
-     * Convert a {@link OffsetDateTime} to a long value.
-     *
-     * @param offsetDateTime the {@code OffsetDateTime}
-     * @return the long value
-     */
-    @TypeConverter
-    public static Long offsetDateTimeToTimestamp(final OffsetDateTime offsetDateTime) {
-        return offsetDateTime == null ? null : offsetDateTime.withOffsetSameInstant(ZoneOffset.UTC)
-                .toInstant().toEpochMilli();
-    }
-
-    @TypeConverter
-    public static StreamType streamTypeOf(final String value) {
-        return StreamType.valueOf(value);
-    }
-
-    @TypeConverter
-    public static String stringOf(final StreamType streamType) {
-        return streamType.name();
-    }
-
-    @TypeConverter
-    public static Integer integerOf(final FeedGroupIcon feedGroupIcon) {
-        return feedGroupIcon.getId();
-    }
-
-    @TypeConverter
-    public static FeedGroupIcon feedGroupIconOf(final Integer id) {
-        for (final FeedGroupIcon icon : FeedGroupIcon.values()) {
-            if (icon.getId() == id) {
-                return icon;
-            }
-        }
-
-        throw new IllegalArgumentException("There's no feed group icon with the id \"" + id + "\"");
-    }
-}
diff --git a/app/src/main/java/org/schabi/newpipe/database/Converters.kt b/app/src/main/java/org/schabi/newpipe/database/Converters.kt
new file mode 100644
index 000000000..0eafcede1
--- /dev/null
+++ b/app/src/main/java/org/schabi/newpipe/database/Converters.kt
@@ -0,0 +1,52 @@
+package org.schabi.newpipe.database
+
+import androidx.room.TypeConverter
+import org.schabi.newpipe.extractor.stream.StreamType
+import org.schabi.newpipe.local.subscription.FeedGroupIcon
+import java.time.Instant
+import java.time.OffsetDateTime
+import java.time.ZoneOffset
+
+object Converters {
+    /**
+     * Convert a long value to a [OffsetDateTime].
+     *
+     * @param value the long value
+     * @return the `OffsetDateTime`
+     */
+    @TypeConverter
+    fun offsetDateTimeFromTimestamp(value: Long?): OffsetDateTime? {
+        return value?.let { OffsetDateTime.ofInstant(Instant.ofEpochMilli(it), ZoneOffset.UTC) }
+    }
+
+    /**
+     * Convert a [OffsetDateTime] to a long value.
+     *
+     * @param offsetDateTime the `OffsetDateTime`
+     * @return the long value
+     */
+    @TypeConverter
+    fun offsetDateTimeToTimestamp(offsetDateTime: OffsetDateTime?): Long? {
+        return offsetDateTime?.withOffsetSameInstant(ZoneOffset.UTC)?.toInstant()?.toEpochMilli()
+    }
+
+    @TypeConverter
+    fun streamTypeOf(value: String): StreamType {
+        return StreamType.valueOf(value)
+    }
+
+    @TypeConverter
+    fun stringOf(streamType: StreamType): String {
+        return streamType.name
+    }
+
+    @TypeConverter
+    fun integerOf(feedGroupIcon: FeedGroupIcon): Int {
+        return feedGroupIcon.id
+    }
+
+    @TypeConverter
+    fun feedGroupIconOf(id: Int): FeedGroupIcon {
+        return FeedGroupIcon.values().first { it.id == id }
+    }
+}