I had a client request to include an iOS Sticker Pack, or iMessage extension, with a Xamarin Forms iOS application. At first it seemed impossible, but after a lot of trial and error with the Ice Cream Builder sample project, I was able to bundle the stickers in the project. Meaning, when a user installs my iOS app, the sticker pack is installed at the same time. This blog post will explain how to bundle a simple iMessage extension with your application that displays a bunch of stickers (GIF & PNG). This blog post assumes you are using Visual Studio to develop your Xamarin iOS application.
Bundling an iMessage app with your main Xamarin.iOS app is actually really simple. Start by adding a new iMessage extension to your solution, as you would normally do for any other type of project (right click solution -> Add… -> New Project). If you don’t see an iMessage extension, you may not have included the necessary project types when installing Visual Studio (I think it comes with the Xamarin package, but I’m not 100% sure).