Well written! I’ve had a similar experience with a habit tracking app. I’ve once stopped using it and after getting back to it after a year or so, it was so much worse with so many new pay walled limitations. An open source habit tracker on the other hand stayed the same for years and was even improved further. If you’re inrerested: Loop Habit Tracker https://f-droid.org/packages/org.isoron.uhabits/
Maybe not exactly what you’re looking for, but this app could be useful someday: https://github.com/ligi/SurvivalManual It’s also available in F-Droid, but didn’t receive any updates for 4 years. It’s basically an easily navigatable pdf that tells you what to do in a survival situation