Yes, user can install multiple respective InstaVR generated apps on single device.This can be accomplished simply by downloading the app. Make sure that the app ids are different for every app to avoid the over writing of one app over the other.
Android - Yes, you can install multiple InstaVR generated Android app
GearVR - Yes, you can install multiple InstaVR generated GearVR app
Daydream - Yes, you can install multiple InstaVR generated Daydream app
iOS - By default, one InstaVR-generated iOS app on your phone is allowed. You can purchase the ability to simultaneously have multiple InHouse InstaVR-generated iOS apps on your iPhone. You will have to buy "Co-existent Multiple Inhouse iOS Apps" add on.
by purchasing one add on, you can install 6 more Inhouse InstaVR-generated iOS apps.