In the last couple of weeks I've been working on Cranki:
Cranki = Crosswords + Anki. (It's a stupid name tbh, haha)
I like doing crosswords in Spanish (to learn vocab) but none of the apps out there allowed me to use my own list of words that I come across. So I built one instead.
It's entirely client-side. No server, no database, no accounts, etc. Your words and stats are stored in local storage.
I built this for myself but let me know if you like it!