We'd like to give a shout out to following open source projects that were used in the SDK development:
A complete, cross-platform solution to record, convert and stream audio and video.
The SyncStage Android SDK is dynamically linked with unmodified libraries of FFmpeg licensed under the LGPLv2.1. The source code of these FFmpeg libraries, the compilation instructions, and the LGPL v2.1 license are provided in Github.
Opus is a totally open, royalty-free, highly versatile audio codec. Opus is unmatched for interactive speech and music transmission over the Internet, but is also intended for storage and streaming applications. It is standardized by the Internet Engineering Task Force (IETF) as RFC 6716 which incorporated technology from Skype’s SILK codec and Xiph.Org’s CELT codec.
A very lightweight WebSocket client library for JVM based clients or Android which aims to implement the WebSocket protocol as defined in RFC 6455. It has no dependencies and the jar file is only 22KB.