Have you ever wanted to write an application that can run on your phone? Time to learn Objective C or Java - or both of them if you want your app to run on both iOS and Android. Want that app to run on your desktop as well? There's another whole stack of APIs to learn. What about a website as well? Add JavaScript, CSS, and yet more APIs to your "to-learn" list. Want to do all this with a single language, and a single API? Good luck with that. And if you want that language to be Python? You've *got* to be kidding.... right? BeeWare is a collection of tools and libraries that allows you to build cross-platform GUI applications in pure Python, targeting desktop, mobile and web platforms. Apps created using BeeWare aren't web apps wrapped in a native shell, and they don't ignore native widget styles and UI conventions - they're 100% native. BeeWare apps are indistinguishable from applications written using the official languages and APIs for each platform. In this tutorial, you'll be introduced to the BeeWare suite of tools and libraries, and use those tools to develop, from scratch, a simple GUI application. You'll then deploy that application as a standalone desktop application, a mobile phone application, and a single page webapp - without making any changes to the application's codebase.