Game crashes on start after upload to google play

Hey there I’m having a problem with running my game after uploading it to google play.
The game crashes upon start - no loading screen or anything.
PIE works fine, just as mobile preview.

Here are the crash reports:

java.lang.NoClassDefFoundError: 
 
  at com.google.android.gms.plus.Plus.<clinit> (Unknown Source)
 
  at com.epicgames.ue4.GameActivity.onCreate (GameActivity.java:2785)
 
  at android.app.Activity.performCreate (Activity.java:7009)
 
  at android.app.Activity.performCreate (Activity.java:7000)
 
  at android.app.Instrumentation.callActivityOnCreate (Instrumentation.java:1214)
 
  at android.app.ActivityThread.performLaunchActivity (ActivityThread.java:2731)
 
  at android.app.ActivityThread.handleLaunchActivity (ActivityThread.java:2856)
 
  at android.app.ActivityThread.-wrap11 (Unknown Source)
 
  at android.app.ActivityThread$H.handleMessage (ActivityThread.java:1589)
 
  at android.os.Handler.dispatchMessage (Handler.java:106)
 
  at android.os.Looper.loop (Looper.java:164)
 
  at android.app.ActivityThread.main (ActivityThread.java:6494)
 
  at java.lang.reflect.Method.invoke (Native Method)
 
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:438)
 
  at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:807)
Caused by: java.lang.ClassNotFoundException: 
 
  at dalvik.system.BaseDexClassLoader.findClass (BaseDexClassLoader.java:125)
 
  at java.lang.ClassLoader.loadClass (ClassLoader.java:379)
 
  at java.lang.ClassLoader.loadClass (ClassLoader.java:312)

And:

	at com.google.android.gms.plus.Plus.<clinit>(Unknown Source:0)
 
FATAL EXCEPTION: MainThread-UE4
 
Process: com.Vicious.BirbHorizon, PID: 9166
 
java.lang.NoClassDefFoundError: Failed resolution of: Lcom/google/android/gms/common/api/Api$zzf;
 
  at com.google.android.gms.plus.Plus.<clinit>(Unknown Source:0)
 
  at com.epicgames.ue4.GameActivity.onCreate(GameActivity.java:2785)
 
  at android.app.Activity.performCreate(Activity.java:6999)
 
  at android.app.Activity.performCreate(Activity.java:6990)
 
  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)
 
  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2731)
 
  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
 
  at android.app.ActivityThread.-wrap11(Unknown Source:0)
 
  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
 
  at android.os.Handler.dispatchMessage(Handler.java:106)
 
  at android.os.Looper.loop(Looper.java:164)
 
  at android.app.ActivityThread.main(ActivityThread.java:6494)
 
  at java.lang.reflect.Method.invoke(Native Method)
 
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
 
  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
 
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.google.android.gms.common.api.Api$zzf" on path: DexPathList[[zip file "/data/app/com.Vicious.BirbHorizon-zw88GliInV17f2HOY1ThEw==/base.apk"],nativeLibraryDirectories=[/data/app/com.Vicious.BirbHorizon-zw88GliInV17f2HOY1ThEw==/lib/arm, /data/app/com.Vicious.BirbHorizon-zw88GliInV17f2HOY1ThEw==/base.apk!/lib/armeabi-v7a, /system/lib]]
 
  at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:125)
 
  at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
 
  at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
 
  ... 15 more

I suppose it has something to do with either my proguard or gradle configuration but I’m really lost here.

Hey, so I fixed the problem.
I had to go into C:\Program Files\Epic Games\UE_4.21\Engine\Build\Android\Java and edit the aar-imports file.
After adding all missing dependencies and updating the others (as many were super outdated) the problem was fixed.

(also make sure the dependencies are the same as those in your plugins build.gradle files.

Is there any chance this is what is causing my error where on launch it crashes because Activity not whitelisted com.epicgames.ue4.GameActivity (something like that)?

I’m getting that same error with my game on Google Play. Any chance you could walk through a bit of what you described for a non-coder?