Got this for a ski chalet holiday with kids.
My advice. Turn off blue tooth and "ask to join networks". Forget any other wifi networks in range.
Once I did this it worked perfectly.
Before it kept dropping the connection as one or the other phone tried switching to a different net work or waiting for me to say if I wanted to connect to one. Also worked more reliably with blue tooth off.
I did pay the money.
Just needs better instructions but I think it's a good way to sell this sort of app. Because if it won't work for you then don't pay.