This chapter focuses on 3D first person shooter prototype and adapt it into a virtual reality (VR) mobile game project. To turn a game into a VR project, camera has to be modified to enable stereoscopic rendering, and the first-person controller needs to be reworked as the player movement will need to be completely rethought according to the Cardboard platform. The chapter discusses menu navigation with two items in VR: one for starting the game and another to switch VR mode on and off. It also describes setting up of a user interface for VR, as well as setting up the Toggle VR button event.