Google Play Services allows your phone to benefit from the latest versions of apps without upgrading your Android operating system to the latest version. It doesn't support all applications, but most Google-developed apps like Gmail, Google+, Google Play, Google Maps are supported.

Google Play Services is not the kind of application we usually see. If you open it, nothing will happen or change. However, the app is installed by default on Android devices. It's a package of APIs that make sure fewer apps are dependent on Android operating system updates to run.