App Crash on Android after publish to play store

The app crashes and I get a popup that says “unfortunately App has been stopped” on all devices.
I get this error

Type

java.lang.RuntimeException
java.lang.RuntimeException: 
  at android.app.LoadedApk.makeApplication (LoadedApk.java:1264)
  at android.app.ActivityThread.handleBindApplication (ActivityThread.java:7086)
  at android.app.ActivityThread.access$1500 (ActivityThread.java:265)
  at android.app.ActivityThread$H.handleMessage (ActivityThread.java:2146)
  at android.os.Handler.dispatchMessage (Handler.java:106)
  at android.os.Looper.loop (Looper.java:257)
  at android.app.ActivityThread.main (ActivityThread.java:8115)
  at java.lang.reflect.Method.invoke (Native Method)
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:626)
  at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1015)
Caused by: java.lang.ClassNotFoundException: 
  at dalvik.system.BaseDexClassLoader.findClass (BaseDexClassLoader.java:207)
  at java.lang.ClassLoader.loadClass (ClassLoader.java:379)
  at java.lang.ClassLoader.loadClass (ClassLoader.java:312)
  at android.app.AppComponentFactory.instantiateApplication (AppComponentFactory.java:76)
  at android.app.Instrumentation.newApplication (Instrumentation.java:1158)
  at android.app.LoadedApk.makeApplication (LoadedApk.java:1256)