These classes teach you how to add user personalization to your app. Some of the ways you can do this is by identifying users, providing information that's relevant to them, and providing information about the world around them.
Accessing Contacts Data
How to use Android's central address book, the Contacts Provider, to display contacts and their details and modify contact information.
Making Your App Location-Aware
How to add location-aware features to your app by getting the user's current location.