I built a free glucose logger that syncs to Cronometer via Health Connect
I'm type 2, and between CGM sensors I'm on finger sticks — which means manually logging readings somewhere. I used to like mySugr, but these days you have to click through a wall of data-sharing consents just to write down a number. For a diabetes app, that felt backwards.
So I wrote my own. It does exactly two things:
- Log a reading (mg/dL or mmol/L, optional time/meal/notes)
- Show history with a 7-day graph
Everything writes to Health Connect, and if you've enabled Cronometer's blood-glucose import, readings show up there automatically — multiple readings a day graph nicely in your Cronometer diary. Backdated entries work too, so you can bring in old data.
The privacy part, since that's why I'm posting here: the app has no internet permission. Not "we promise not to share your data" — it architecturally cannot phone home, and you can verify that in the manifest yourself. No account, no ads, no analytics, no server. Notes never leave the device; only glucose value, timestamp, and meal label go to Health Connect.
It's free and open source (Kotlin, Android 9+, needs Health Connect). APK is on the releases page if you don't want to build it:
https://github.com/hazlema/glucose-log
Built it for myself, sharing in case it's useful to anyone else doing serious tracking. Happy to answer questions or take feature requests, though fair warning: the feature list being short is on purpose.