VR2 stands for PCBest VoIP Recorder2. 
This is a C# project developed by PCBest to use its VoIP Recorder SDK for end users.
It is also a good sample for developers about how to use this API.

Subfolders:
VR2                -> All classes to implement the feature
VR2Svc             -> Windows service wrap for run VR2
VR2Test            -> a EXE to run VR2(PCBest VoIP Recorder2) instead of Windows service.
VR2WinApp          -> Since version 2.10, it is introduced to replace VR2ManageClient. It can run independently like VR2Test, but with interfaces. 
Also, it can run as a Windows service.