Google is pushing out a new version of Google Play Services today. The update looks to be a pretty basic affair, with enhancements to the Google Analytics API and the Google Drive API, but changes to the Google Fit API means we have a new version of the L developer preview with the latest Google Fit API included.
Google Play services 6.1 adds Enhanced Ecommerce analytics support from Google Tag Manager and offers new improvements to the Google Drive Android API. With the latest release, we're also including a refresh of the Google Fit developer preview, so that you can test your fitness apps on any Android device.
The new Google Play Services update will, in typical Google fashion, slowly roll out to all of us with no required action on our part. For more details, see the source below.
Source: Google Developers blog