For an app developer, providing a seamless user experience is critical for building engagement and growing a user base. Passwordless login solutions provide your users with a simple, secure, and positive first experience.In this course, you'll learn two frameworks for sign-up and authentication: Account Kit, which uses a phone number and code, and Facebook Login for Android. You’ll learn how to configure both types of authentication side by side in a sample app, test the flow on a series of common use cases, and wrap things up with an introduction to Facebook’s Graph API, a window into an incredible wealth of data for creating a more engaging experience for your users.