Code
Orbot for Android
The primary code is available on GitHub and Gitlab
Orbot for iOS
The primary code is available on GitHub
Tor-Android
Orbot builds on the core Tor-Android library which allows any app to bundle and manage Tor inside of it
Tor.framework for iOS
Orbot for iOS builds on the core Tor.framework project, which is available as a CocoaPad for any application to integrate
IPtProxy
Orbot also includes support for Tor Pluggable Transports, like Obfs4 and Snowflake using the IPtProxy Library