You've built a Xamarin app and want to release it on the App Store and Google Play. To do this, you need to create an iOS distribution provisioning profile and distribution certificate, configure your release build, set up iOS bundle signing, create an iTunes Connect record for your app, and build and submit your app. For Android, similar steps are required, including configuring your release build, compiling and building your app, and signing and distributing the APK. Both Apple and Google review apps before they're available on their stores, so be patient with the process.