Smart Places is an Android app that executes actions based on the user's location.
This app idea won 2nd runner up at Here Hackathon 2014.
Send messages to your loved once you arrived a certain destination to let them know that you're safe.
Set reminders the next time you're in a specific address or nearby an establishment type.
Silence ringer in campus? Turn on WiFi in office?
The app changes device settings automatically based on your location.