I'm thinking about making a simple cross-platform, open-source app! Desktop/web/mobile both

Mostly because I wanna play with Tauri

- but I also wanna make something I might actually use / other people might use :)

My ideas:
A) yet another pomodoro/take-breaks app
B) a generic event sign-in app
C) a video playing app that helps you loop sections to practice (dance, singing, playing instruments along with it)
D) a "sticky note" task-focus app like my app intentionize.me