So refund in full and do the rest? That's what happened anyway, isn't it (the refund)?

The point was there were options, but the creator didn't seek them. So many people wanted that app to continue living - I find it impossible to believe the creator couldn't get an extra $1 a month (or even a lot more!) from those users.

How many apps can boast they have 50,000 paying customers? People need to appreciate just how difficult of an accomplishment that already is. The paying users loved the app, and would have paid more to continue using it - especially in light of the available information at the time.