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The [OTSubscriber subscribeToAudio] and [OTSubscriber subscribeToVideo] messages are unsupported.
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OpenTok on WebRTC provides increased connectivity.
Release 2.1.2

Fixes for:
- Support for Mantis, the OpenTok media server for WebRTC.
- Bugs related to backgrounding the application.
- Added native support for armv7s architecture
- Fixed a bug that causes inconsistent UI when manipulating
  media track functions (eg. publishVideo, subscribeToAudio, etc.)