Sip2Go is a new communication solution designed to replace traditional SIP clients on Android devices. It addresses common VoIP issues such as high battery consumption, unstable sessions due to changing IP addresses, and complex NAT traversal. The system functions by separating the mobile application from the SIP infrastructure.
The architecture utilizes a gateway that connects to the PBX as a standard SIP endpoint while communicating with the mobile app via secure WebSocket (WSS/TLS). This setup allows the mobile client to use the Opus codec for audio, while the gateway handles transcoding to PCMU/PCMA for the PBX. The app uses FCM push notifications to wake up for incoming calls.
The system supports session recovery, allowing calls to persist even if the network connection is interrupted or the application restarts. Configuration is simplified through a QR code or link system, similar to eSIM activation. The project is open-source, and users can deploy the gateway on their own infrastructure using personal Firebase credentials.
The software is provided free of charge for those who build the application themselves with their own Firebase keys. Currently, the solution is available only for Android, as there is no iOS version or development support for Apple devices at this time.
