At the moment I am working on two open source with MIT license (free to use for everyone :) )

Rook - it is Unreal 4 plugin which integrates OpenAL Soft. The reason for that was to add EAX and emulated reverb effect to Unreal 4 apps

UMC - Universal Motion Controller is an attempt to make any AR anabled mobile phone become motion controller under Unreal 4 and Unity3D

While Rook is preatty mature and require only some additional work and maintance, UMC is still in very early stage of development and 'need some love'.
Plans for Rook:

• HDR
• Mixer
• Remove virtualizating of multichannel - play audio source on specific audio channel

Plans for UMC:

• exchange UDP to TCP connection - in work at the moment
• proper support for multiply devices
• art improvments
• R&D of other tracking possibilties