Developing holographic apps is as simple as building for the Universal Windows Platform. All holographic apps are Universal Windows apps, and all Universal Windows apps can be made to run on Microsoft HoloLens. With Windows 10 and familiarity with middleware tools like Unity, you can start getting ready to build holographic experiences today.
In addition, we have released documentation and forums specific to HoloLens. Keep checking back as more is available all the time.