Linux Phones

This sounds a lot like the Flattr model - a service that had its moment in 2010/2011, but ultimately failed: https://en.wikipedia.org/wiki/Flattr

Payments are a challenge, with processing fees and taxes in an international context, small sums don't work out well - there's a reason why services like Liberapay push you to do bigger amounts at one time instead of small amounts at multiple points in time.