I’m working on a better SRS-based flash card app. I know there’s Anki and some solutions online, but I have not been able to find a good app-based solution (I.e

I’m working on a better SRS-based flash card app. I know there’s Anki and some solutions online, but I have not been able to find a good app-based solution (I.e. make your own cards, with no service subscription). Most of the flash card apps out there have awful UI. I’m trying to make mine the most easy to use and powerful flash card app.