Description
Cairn is a body-measurement tracker for Android and Wear OS, built around Android’s Health Connect platform rather than an account or a cloud service. Weigh-ins, body composition and heart rate are logged straight into Health Connect from the phone or the watch, and the dashboard reads back whatever the watch has already recorded for steps, calories, exercise and sleep — so everything lives in one place without Cairn ever needing to collect it itself.
What it does
Dashboard at a glance — weight, BMI, body fat %, body water %, current heart rate and last night’s sleep, all on one screen, backed by Health Connect rather than a private database.
Wear OS quick-log — add a weigh-in from the watch app without reaching for a phone.
Continuous heart rate, on your terms — optional watch-driven monitoring with today’s min, average and max plus a full readings graph, switched on and off from the watch itself.
History that’s actually readable — every past measurement and heart-rate session in one list.
Privacy by design
Cairn has no account, no analytics and makes no network calls of any kind — there is no server for your data to reach in the first place. See the Cairn app page for screenshots and the full privacy policy for a record-by-record breakdown of what it reads and writes.
Try it
Cairn is currently in closed testing on Google Play — sign up on the Play Store listing to get access.
View application
