Triggering camera usage in ios face app

hi guys, relatively new here so apologies if this is already being said and solved.
I’m all set with a simple avatar scene/project that works fine with live link etc. I’m also all set with the apple developer side of things (nightmare). I’ve also managed to deploy an app to my iphone from Unreal 2.7. The only thing I’m missing is the automatic connection between the iphone camera and the app/avatar, in order to read the facial motion capture.
is there anything that needs to be done in unreal?
I also tried (successfully) to deply an app copy of the faceAR demo and have the same final problem: the app starts fine but doesn’t “start” the camera.
Or do I simply need to “publish” the app on the app store, sot he iphone reads it as regular app, so we can “allow” access to the camera?
thank you in advance!!


I meant Unreal 4.27!!