Sometimes you don't want people submitting songs that aren't even in the venue. It can get out of hand with people just entering the venue and singing within 5 minutes. People who have been there buying drinks and food for the last hour waiting to sing can get very upset. This feature just forces singers to use the venue's wifi for submitting their songs by phone. Of course you can enter their songs manually as well(watch video to the end). Wifi Constraint is also a feature on Karaoke Manager which comes with a catalog for your users to browse. The demo below demonstrates this feature in action for Karaoke Queue Manager.