Used to integrate Android apps with Facebook Platform
This open-source library allows you to integrate Facebook into your Android app. Integrate your Android app with Facebook to build engaging social apps by using the Facebook SDK for Android. To learn more about using Facebook development tools. The current version of the Facebook SDK for Android is version 11.2.0 and requires the Android API 15. Code and samples for the Facebook SDK for Android are available on GitHub.
Functional Bluetooth GATT for Android (all the meanings)
...This library makes it possible to have readable and debuggable code that interacts with Bluetooth Low Energy GATT (General Attribute), that is, the connection part of the Bluetooth Low Energy standard.