Please don't pin your play-services dependency at a particular version

It causes issues with other libs when a 3rd-party library, like yours, pins its play-services dependencies at a particular version.

eg:

Unknown source file : com.android.dex.DexException: Multiple dex files define Lcom/google/android/gms/iid/MessengerCompat$1;
Unknown source file :   at com.android.dx.merge.DexMerger.readSortableTypes(DexMerger.java:596)
Unknown source file :   at com.android.dx.merge.DexMerger.getSortedTypes(DexMerger.java:554)
Unknown source file :   at com.android.dx.merge.DexMerger.mergeClassDefs(DexMerger.java:535)
Unknown source file :   at com.android.dx.merge.DexMerger.mergeDexes(DexMerger.java:171)
Unknown source file :   at com.android.dx.merge.DexMerger.merge(DexMerger.java:189)
Unknown source file :   at com.android.dx.command.dexer.Main.mergeLibraryDexBuffers(Main.java:502)
Unknown source file :   at com.android.dx.command.dexer.Main.runMonoDex(Main.java:334)
Unknown source file :   at com.android.dx.command.dexer.Main.run(Main.java:277)
Unknown source file :   at com.android.dx.command.dexer.Main.main(Main.java:245)
Unknown source file :   at com.android.dx.command.Main.main(Main.java:106)

You have

compile 'com.google.android.gms:play-services-gcm:8.3.0'

You need to change it to:

compile 'com.google.android.gms:play-services-gcm:+'

[christocracy]

In addition, I question the wisdom of including the entire ‘play-services-gcm` just to fetch the gcm identifier. This should be the responsibility of some other module which is doing Push requests. This module has no business dealing with this.

[GantMan]

ty @antoinerousseau