Telegram is a messaging application for mobile and desktop devices. Besides an Android SDK, Telegram provides a supported third party kit developed by Stepan Korshakov. This alternative named "S edition" is a version based on open-source telegram-api, mtproto and tl-core libraries. Instructional content displays how to build variants and how to build sources. Telegram API documentation is available in English and Russian languages. Just like the official Android app, this resource aims to help developers in building mobile applications with improved accessibility, security, and functionality.