Hey! I'd be interested in working on this. My suggestion would be to use Flutter for front-end (React Native is perfectly fine as well, though) and especially to utilize an API like Pledge's one for back-end (as they've solved the tough parts of the donation process already and they don't really have any service fees when it comes to this use case). Coincidentally, I have roughly 10 years of experience of hobbyist game design, so we could think about adding e.g. prosocial features and mechanics down the line if you're interested.
Thanks for the reply!
I'm aware of the thread and I believe that we'd be able to solve the policy issues. Using an existing API like the Pledge's one mentioned above would be my strong recommendation, given that they indeed handle the heavy parts of the donation process. It would make dealing with the policies of the app stores a breeze compared to making the back-end from scratch, as in that case there would be a rather huge workload in dealing with the heavy (although necessary) bureaucracy.
It would be nice if we started coordinating the development somehow. I would start with a central hub where all the comms would take place so that the discussion wouldn't become scattered and hard to follow. Maybe something like semi-open Slack or Discord server for more instant and spontaneous messaging and all the fancy extra features?