Hi, we're using Unity 5.6.3f1 and we have an Android project that uses the following plugins: FacebookSDK 7.10.0 Heyzap 9.12.5 integrated with AdMob, AppLovin, Chartboost, Vungle and UnityAds GameAnalytics Recently we have switched to Gradle build to avoid the DEX-limit error returned by the default Internal build. After some conflict resolutions, all was ok. We've tried to add Fabric Crashlytics to the project, and now we have the following error with Gradle: FAILURE: Build failed with an exception. * What went wrong: Execution failed for task ':transformClassesWithDexForRelease'. > com.android.build.api.transform.TransformException: com.android.ide.common.process.ProcessException: java.util.concurrent.ExecutionException: com.android.dex.DexIndexOverflowException: method ID not in [0, 0xffff]: 65536 I've found this interesting thread: http://answers.unity3d.com/questions/1301593/android-gradle-build-error.html Here they suggest to Export an Android Proect using Gradle, copy build.gradle file, enable multidex and save it under Plugins/Android/mainTemplate.gradle. This approach seems to solve the problem, but is it a safe solution?