Building Xamarin Android apps with Azure Mobile Services offers a complete end-to-end platform for implementing mobile apps. While the Android platform offers some inherent security protections, developers are on the hook for implementing security within their applications. This presentation will focus on using Android and .NET APIs for building secure apps written in C#. We will first take a look at the architecture and security model for Android. We will examine how to securely store data on a device, how to communicate securely, and how to implement cryptographic solutions. Strategies for authenticating and authorizing users with Azure Mobile Services will be demonstrated to protect access to your application and data. Third party security libraries will be discussed, along with example implementations. The goal of this presentation is to leave developers with a set of security controls that they can build into their own applications without reinventing the wheel.