In this article I'll show you how to add Facebook authentication to the "RememberIt" mobile application. If not yet done, please read the previous post in the Hands on Xamarin Platform Pipeline series. Facebook app creation In order to be able to add Facebook authentication, we need to create a Facebook App. To do this, navigate to: https://developers.facebook.com/apps , click on "Add a New App" button then fill in the application information. Go to Settings then copy the App ID. Then always in Settings, click on Add Platform then Select Android. Fill in the following information: - Google Play Package Name: the package name defined in Android Manifest file. - Class Name: MainActivity in our case. - Key Hashes: where we can add Debug and Release Android key hashes. To generate the Debug Key hash, open the terminal then run the command below: Use 'android' as password then copy-paste the generated hash key. Now, click on Add Product under Products catego...