Hey guys! (First of all sorry for my english)
I’m working on a little VR experience for an university project and I’m desperate. I’ve been having the same problem with FBX models, when I put one on my scene the Gear VR turn in black and then the Samsung “Home” it starts, but my project not. When I execute it without any fbx or obj on it, it works perfectly: empty, of course, but it works. And if I add any default mesh from unreal, like a basic cube, it works too.
Could anyone post the correct FBX import options for Gear VR? Or any other solution for my problem…
PD: Once I get it to work but I dont remember what I did. 
I’m sorry, I did not get it: does the whole scene turns black, or just the object of the fbx you imported?
If the whole scene is black on start, and then the Samsung “home” app appears, without you doing nothing, then your app crashed. I don’t know what kind of fbx could cause a crash (never happened to me). What kind of fbx are you trying to import? What program did you use to create it? The default fbx import options always worked fine, for me.
Thanks for the answer ocramot. Finally, I solved de problem but I used a strangly method to fix the issue.
When I import a fbx to UE4 and then I cook the app in my smartphone the Gear VR turn in black (the screen, nothing appears neither map or assets) and then the Samsung “Home” it starts, but my project not, it seemed not detected or something like this. But finally if I restart the project in UE4 and I return to reload the same app on my smartphone, it works!
The problem has been solved reestarting the project with the assets imported previously.
Good for you that it worked! 
probably there was something strange during the import process. Anyway: yes, if your app is black when you start it, and then the Home screen appears, it means that your app crashed on start. Not sure why, but Logcat could contain some useful info, if you’re curious and you want to find out