Google just let developers know, via the Android Developers Blog, that an update to Google Play services has begun to roll out. You may see your phone update any time over the next few days, but don't expect to see immediate benefits.
Google Play services is a set of under-the-hood features for developers. Android developers deploying apps to phones with Google Play (read: not those really cheap Android Open Source Project phones with no Play store access) can call upon Google's enhances application programming interfaces (APIs).
New this this release, for example, is Street View access for those using Google's Maps. A developer making an app that uses map data can now show the Street View for a location, including control over zoom and rotation. The Indoor Maps feature has some new options for developers, too.
There's an activity tracking API that developers can use to tell when a user is stationary, in a car, on a bike, or on foot. In the 4.4 update, it can even tell if you're walking or running. The update brings additional minor tweaks to Game Services, Mobile Ads, and Wallet Fragments, too.
Bigger enhancements to Google Play services are likely coming soon, judging by the way Google chose to end its blog post:
Coming up in June is Google I/O, no need to say more…