Learn how to build and deploy a custom JWT authentication system using Ktor, MongoDB, and Android in this comprehensive video tutorial. Discover the intricacies of implementing JWT tokens for user authentication in your app. Follow along as the instructor guides you through creating a Ktor backend, developing an Android application, and deploying the server to an Ubuntu environment. Gain hands-on experience with practical code examples and access the provided source code repositories for both the Ktor backend and Android app. By the end of this tutorial, you'll have the knowledge to create your own robust authentication system and deploy it successfully.