Thanks for your feedback! 🐦🐦
Right now I have a very loose "subscription model" if you want to schedule posts more than 7 days ahead or you already scheduled 10 posts you would get a popup, but you also have a "use for free" button. So anybody can basically use the app for free without limit.
At this stage I would prefer people to feel free experiment with it, and have donations from users genuinely interested in support the development.