Here’s something I’ve compiled from other peoples’ projects that seems to work quite well on SamsungGearVR.
If you have any questions, suggestions -if you use it, just mention the ue4 community !!
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https://youtube.com/watch?v=yA9AspoC_Z8
size=2.58mb
I borrowed vrom the Solar System project 
Thank you very much, it is useful. However, Oculus Home launches immediately after I plugged in gear vr. Anyway, to solve this? I have been searching around and no luck.
You should add Oculus Key file generated from Oculus Store for your phone to the Engine (Android Assets), then setup project to use Gear VR in Platforms - Android (just enable: Configure the AndroidManifest for deployment to GearVR), then deploy app at your phone and run it. If problem will still exists you can try to turn on Developer Mode in Oculus Service at mobile and try to run app without GearVR and if you see that your app is not running then look to Log (via for e.g. android monitor) and see what the problem is.