I am using the cash app for playing poker in my country on a website that has poker. you can deposit your bitcoin with lightning wallet bitcoin. please try what I mean ignitioncasino.eu
I think grin have a cash app for playing,call ironbelly or something like that.but it is Interactive trading,Transactions cannot be sent directly。
and ardocrat have creat Grim - Cross-platform GUI for Grin,have you try?
well I move the bitcoin first from the cash app to phoenix wallet for lightning. the experience is easy for anyone to use. very much QR code and copy and paste the codes.
User’ feedback to developers is improving better software products.maybe you should try grin’sgrim wallent，then feedback to david and ardocrat.
We can use QR to scan address and amount, but Slatepack size can be huge so we use files here. If payment will be integrated on the website https link with exposed wallet API can be enough (not implemented https support at GUI yet).