Koyomi

Health apps that keep your data on your phone.

Koyomi makes free, open-source apps for tracking your health. They work offline, need no account and show no ads.

See Kitae, our workout tracker

Kitae鍛え

A workout tracker. Plan your training days, log every set and watch your lifts climb. The rest timer follows you onto the Lock Screen.

Back up to a plain zip file and restore it on Android or iPhone.

Kitae's activity grid: one square for each day, filled in when you train. This one is an example.

How we make apps

.offline
Everything works without a connection. Your data is a file on your phone, and backups are plain zip files you keep wherever you like.
.open
The code is open. Read it, build it yourself, or send a fix or an idea to the app's repository.
.private
No accounts, no ads, no tracking, and this website sets no cookies either.