A couple of times, I’ve found it necessary to know what version of google play services I’m dealing with. For example, when I was using a number of Titanium modules that were dependent on google play services, I had version conflicts. But Google Play Services versioning is a nightmare. This article tries to make sense of it all.
Google publishes Google Play Services in the Play store with version numbers like 5.0, 6.1, and 6.5. But the versioning used for developers in the Android SDK Manager is completely different: r19, r21, and r22.
To make matters worse, the google_play_services.jar file has no version number
at all; there’s nothing I could find inside of the jar file that exposes either
version number. So identifying a jar file that somebody bundled with their
project is nearly impossible.
I’ve compiled everything I could find about each version: its version numbers (as listed by Google and as displayed in the Android SDK manager), its release date, and the jar file size and MD5 checksum so you can identify your own jar files.