java.lang.NoClassDefFoundError exception on some devices
It seems that your app reach the limitation of 65K methods, which is quite famous limitation of Android.
Ref: https://developer.android.com/tools/building/multidex.html#dev-build
You can follow the solution in above link. Or in short:
If you have your Application class (you extends class Application), override attachBaseContext() in that class and call Multidex.install(this)
otherwise add this to your Manifest:
android:name="android.support.multidex.MultiDexApplication"
inside <application>
tag.
Please reply here if it solves your problem. It solves mine actually.