Google Play Services 7.3 is currently rolling-out with various bug fixes. If you've used Android Wear with your phone, you'd have noticed the annoying persistent notification that sits in your phone's notification drawer forever.
With this latest Google Play Services 7.3 update, Google has gotten rid of the notification. This means there isn't another notification sitting permanently in your notification drawer that you couldn't get rid of anymore.
The update also brings an updated UI for configuring Trusted Places, the feature that allows your phone to stay unlocked in a certain location. You can now choose on a map the location instead of simply typing it out and it shows the area with a blue dotted circle on the map that is the safe zone. The update also adds a new pull-to-refresh animation in the Google+ app.
If you don't want to wait for the update to hit your device, Download the Official APK below. To figure out the right version of Google Play Services for your Android device, go to Settings -> Apps -> Google Play services, and look at the last 3 numbers in the parentheses. You'll see something like -XYY where X is 0 for pre-Lollipop and both 4 and 7 for Lollipop+, and YY is a specific variant id. -738 means you need the APK that has -738 and so on.