Now a days, many mobile phone, like Samsung Galazxy Note 5, Note 5, Sony Z5...etc already support 4K Video in their camera, however, it looks like the video resolution in DJI GO for OSMO Mobile still only support 1080P at max. Because of this, if we want to shoot 4K video, we cannot use DJI GO, and can only use the built in camera apps in the phone. That means some other DJI GO features, e.g. active tracking, using the button on the Gimble to to start/stop recording...etc cannot be supported.
Is there any plan for DJI to improve this in sub-sequency DJI GO release?

In the DJI GO 3.1.1 there is a bug. Yesterday I tested it with my iPhone 6s plus - not 4k, only 720p 30fps and slow motion is missing
For photo there is panorama missing

My mistake!!!
All ok, I changed to front camera!!!

Delete app then reinstall. It worked for me

CarloUK Posted at 2016-12-8 00:40
Delete app then reinstall. It worked for me

No, it worked for me also perfect. I made a mistake. I changed to the face camera and there is no 4k Resolution.

Reinstalled V3.0.1, still not working. Max resolution only 1080P.

Samsung 7, 7 Edge, 's 4K is supported,  so is iPhone's.   R&D will work on other phones .