I made Mochi[0] as an alternative to Anki, also tackling basically the same problem as OP. The app is based around markdown note/flash cards, but also has a lot of other features inspired by Anki and its various add-ons.
A little bit of feedback if you dont mind:
- Allow to deactivate the notifications for reviewed cards and the info on pressing the space bar. They can get annoying pretty fast.
-At least for the desktop browser version put the preferences in a normal page, not a modal. It was a pain to scroll down since I use only a shitty trackpad,so no mouse-wheel.