This is the repository for the official iOS App for Mastodon. You can install it from the App Store now. You can build the app from source and file bug report here.
Read this blog post for this app to learn more.
Thanks to these open-source projects listed here.
This project is released under the GPL-3 License. It is also dual-licensed to Apple for the purposes of publishing the app on the App Store. For this reason, any contributors are required to sign a Contributor License Agreement.