In our beta tests using Gear VR, the back button and volume buttons work as requested. But when submitted to review, the "reserved interactions test" fails with the following message:
A back button long-press (greater than 0.75 seconds) must bring the user to the Universal Menu.
A “back” action is interpreted by the application dependent on its current state, but generally it will retreat one level in an interface hierarchy. The short-press should provide a custom confirmation dialog which allows the user to exit the app and return to Oculus Home.
Your volume buttons must adjust the volume using the VR volume UI provided by the Oculus Mobile SDK. Currently, your volume display does not function as expected.
Got a similar response, about home and volume buttons not working properly. All mentioned buttons do work fine on our side (just as described in the response). We even tested in one of the mentioned phones (Samsung S6) in the review response.
No it wasn't added (everything was working okay still). But I added OVRManager to the scene (to camera) and submitted a build again. We just got the same "Reserved Interactions Test" warning in the review.
The weird thing is that, "Reserved Interactions" just work exactly described in the fail message, in our test device (S6 with up to date Oculus app). We cannot reproduce the failing state.