Don't understand – VRPlayer : 2D 3D 360° Video Review

How are you supposed to import video from your camera roll onto this app on iPhone? I can't figure it out and the help website (which I hade to manually type the URL for, seeing as it doesn't allow you to copy and paste it) was no use. Please help.
Review by Is this a newer app of theirs? on VRPlayer : 2D 3D 360° Video.