Samsung PixelTrac

This app tracks a printed pattern using a smartphone camera to estimate its position and orientation. The estimated position is then transmitted via bluetooth to any paired device, say, a VR headset. In case of a VR headset, it can be used to render a virtual scene from a desired viewpoint relative to the user’s head.

We use openCL based GPU programming and extremely efficient algorithms to make tracking real-time and thus viable.

See full description at: https://github.com/Samsung/ColorPatternTracker. This app is referred to as the Tracker app.
Please specifically note the "Direct installation" and "pattern printing instructions".

Use the bluetooth library or VR apk or Unity GearVR scene in github repository to receive the 3D coordinates and use them appropriately.

*** This app only works on Galaxy S6. For other phones please refer to the github repository.