Flathabits looks great. I used to use a paid iOS app until they pushed enough UI changes and buggy updates to motivate me to create my own bare bones solution. Wish I had seen your app before that.
Thank you! Hey, looks like you found what works for ya, which enables you to stick to your habits. Well done! I was initially tracking in an org file, but relying on my laptop for tracking was too much friction. Mobile did the trick for me.
(Mine is just a personalized spreadsheet, https://pasteboard.co/PB1theDENEu7.jpg)