BlenderVR is an open-source project framework for interactive and immersive applications based on an extension of the Blender Game Engine to Virtual Reality applications. BlenderVR is a generalization of the BlenderCAVE project, accounting for alternate platforms (e.g., HMD, video-walls). The goal is to provide a flexible and easy to use framework for the creation of VR applications for various platforms, making use of the existing power of the BGE's graphics rendering and physics engine. Compatible with 3 major Operating Systems, BlenderVR has been developed by VR researchers with support from the Blender Community. BlenderVR currently handles multi-screen/multi-user tracked stereoscopic rendering through efficient low-level master/slave synchronization process with multimodal interactions via OSC and VRPN protocols.