If you start the App first on a HoloLens and then on Project Tango Device, while in the same network, the app will automatically connect to the HoloLens.
When successfully connected you can sync the mind map using the sync button located in the menu (just look down).
From then on both users will edit the same mind map and share the work.
See Link below for HoloLens Version
https://www.microsoft.com/de-de/store/p/holo-mind/9pckxxgx6jtn
9Apps 4.9
