I think the “hot take” that needs to be said here - and surprisingly I have not come across it yet - is that it’s totally fine if you’re willing to pay 20 dollars for the app.

However, please remember that the app itself is not self contained. It relies on the hard work of the Lemmy developers and the instance you use staying online. Please consider sending them some money as well down the line. If you get the app for 20 dollars as a one time payment, maybe some future payments - even if considerably smaller - can go towards the latter.