The appropriate lens distortion can be calculated using the Cardboard VR SDK.
It tracks rather well, nearly as well as the GearVR setup. Depending on where you are on earth, the gravity differs so this blueprint accounts for that as well.
If you don’t want to (or can’t) fork over 200$ for Samsung Gear VR, then this is a workaround that lowers the cost of entry for VR (enable Developer mode).