A personal fork of InfiniTime, the open source firmware for the PineTime, with one goal: make the watch record sleep on its own and hand the recording to a companion app afterwards.

The work lives on the infinisleep-health branch. The other half is Gadgetbridge-infinisleep-tracking, the companion app that collects what this firmware records. Neither half is useful without the other.

Ready to install, no toolchain needed

Built firmware is published on the Releases page. Download the pinetime-mcuboot-app-dfu-*.zip from the newest release and flash it straight to the watch. There is nothing to compile and no docker image to pull.

• From the phone, open the zip with Gadgetbridge, which knows how to send a PineTime DFU package. Stock Gadgetbridge does this, not only the companion fork.
• From a computer, python dfu.py -z pinetime-mcuboot-app-dfu-<version>.zip -a <MAC> --legacy, using the dfu.py from the InfiniTime repository. The one from wasp-os fails with a UUID error.

Those files are compiled by me, on my own machine, from the commit each release names. No CI produced them, they are not signed, and nothing about them is reproducible beyond the fact that the source they came from is right here. If you would rather not take my word for it, the build instructions below produce the same thing from the same commit.

Flashing an interrupted DFU leaves the watch in its bootloader and it can be flashed again, so this is recoverable, but it is still firmware. Read the upstream flashing notes if it is your first time.

Why

A stock PineTime can only report what it measures at the moment something is listening. Sleep happens exactly when the phone is least likely to be connected, so sleep charts stay empty no matter what the watch measured. This fork gives the watch a small log of its own and a way to hand it over later.

It builds on two upstream efforts, neither of which is merged:

• PR 2174, InfiniSleep: SleepTk Port by cyberneel, which this fork is based on. It adds the Sleep app, the sleep cycle goal and the gradual wake alarm.
• PR 2304, Add Sleeptracking by sillydan1, a smaller independent take on the same problem, which logs to a file on the watch.

What this fork adds

• A heart rate reading taken at each tracker epoch, rather than a setting that promised one and did nothing.
• An actigraphy count accumulated from the accelerometer.
• A ring of 341 records (timestamp, motion, heart rate, kind), stored packed at 6 bytes each and mirrored to /.system/activity.dat so it survives a reboot. About three and a half nights at a 5 minute epoch.
• A BLE service, 00060000-78fc-48fe-8e23-433b3a1942d0, that hands the records over in batches and only reclaims the space once the host says it stored them.
• Both sampling rates as settings, on a new Sensors page in the Sleep app.
• Heart rate measured on a timer outside any sleep session, every 5, 15, 30 or 60 minutes, set from a new entry in the settings menu and off by default. It stands down while the sleep tracker runs and only measures with the screen off, so it never takes the sensor from the heart rate app.
• Awake time told apart from sleep within a session. A button press or a wake gesture during the night marks the next 15 minutes awake, and the 5 minutes before it, since waking is not instantaneous. Two of them within half an hour mark the whole stretch between. A wrist raise deliberately does not count, because rolling over triggers it.
• A marks page, reachable by swiping up from the tracking page while a session runs, with a Not asleep yet button. It rewrites everything since the session started as awake, for the night that begins with an hour of reading in bed.
• Sessions under five minutes discarded rather than handed over, and one awake record written at each end of a session, so a companion app charts the stretch that was tracked instead of everything back to the previous sample.
• A backoff below 25 percent battery: the epoch floors at 30 minutes and the accelerometer poll at 1 second, so the tracker does not flatten the battery before morning, and the log is written to flash on the way past that threshold so a battery that dies at 4am does not take the night with it.

The BLE service is deliberately kept independent of how sleep is tracked, so it could be reviewed on its own.

Motion tracking is untested, because this watch's accelerometer is broken

The BMA accelerometer in the unit this was written on never answers on I2C. It reads back a chip id of 0x00, the About screen shows Accel. ??? 00/2, and the same bus reads the touch panel's ids correctly, so the bus is fine and the chip is not. Draining the battery flat did not clear it either, which rules out a latched state.

The motion code is written and shipped anyway, for watches whose sensor works, but it is off by default and has to be turned on from the Sensors page in the Sleep app. Until then, records report 0xFFFF, meaning not measured. The firmware also refuses to wake the accelerometer overnight when no sensor answered at boot, so turning the setting on costs nothing on a watch like this one.

Anyone reading this should treat the motion side as unverified on hardware. Heart rate, the log, the BLE transfer and the settings do work.

Companion app

Gadgetbridge-infinisleep-tracking, branch infinisleep, is the companion app for this firmware. Stock Gadgetbridge does not know about this service and will simply ignore it, so the log stays on the watch until it is overwritten.

There is no need to uninstall the Gadgetbridge you already have. The fork builds under its own application id, so the two sit side by side on the phone and keep separate databases:

./gradlew assembleMainlineNopebble
adb install -r app/build/outputs/apk/mainline/nopebble/*.apk

Building

Unchanged from upstream, so the docker route from doc/buildWithDocker.md works as it does there:

git submodule update --init
docker build -t infinitime-build ./docker            # once, and it takes a while
docker run --rm -it -v ${PWD}:/sources --user $(id -u):$(id -g) infinitime-build

The flashable file lands in build/output/pinetime-mcuboot-app-dfu-<version>.zip. Send it over BLE with the dfu.py from this repository, not the one from wasp-os, which fails with a UUID error:

python dfu.py -z build/output/pinetime-mcuboot-app-dfu-<version>.zip -a <MAC> --legacy

Gadgetbridge can install the same zip from its firmware update screen.

One warning specific to this tree: an incremental build can miss a header change and silently link object files that disagree about the layout of a class, which corrupts RAM at runtime rather than failing to build. Delete build/ when a header changed.

tests/activity/run.sh          # activity log tests, on the host: no hardware, no docker

Commits in this fork

Oldest first, as conventional commits. The history was squashed into one commit per subject, so bug fixes are folded into whatever introduced them.

• cfc4ec5f feat(motion): report why the accelerometer failed to initialise, on the About screen
• 0f0ad621 feat(activity): keep a log of recorded activity and serve it over BLE, with host tests
• 2dcd595e feat(infinisleep): write one activity record per tracker epoch, with heart rate, motion and a low battery backoff
• 8418c4ff feat(infinisleep): rework the sleep pages and add a Sensors page
• 971d979b chore: drop four games for flash, and ignore the local build helpers
• e31ae1b4 feat(infinisleep): put the sensor settings on top of the sleep pages
• 3a7fd504 fix(infinisleep): make the Auto button set the wake up time and nothing else
• ae0fc430 feat(settings): add a heart rate polling interval to the settings menu
• 67d2cbdf feat(activity): measure heart rate on a timer outside sleep sessions
• 9a571a29 fix(infinisleep): disable the wake alarm when the tracker is stopped
• 574002b3 chore: drop the Metronome app
• 5aaaebf8 feat(sleep): show the activity log record count on the Info page
• f5f2b860 fix(activity): stop publishing self started measurements as live heart rate
• ca0976f6 feat(sleep): add a log page showing what is waiting to be collected
• 5839e9ca feat(activity): record when a host last asked for records
• 8baf09cd feat(activity): record the quarter hour after a look at the watch as awake
• 1f0cfe37 feat(activity): let the log take records back from the newest end
• e23dd77a feat(infinisleep): discard a session that lasted under five minutes
• 59267b6d feat(activity): bound a session with an awake record at each end
• 1f3666c1 feat(activity): let the log rewrite the kind of records it already holds
• 4f745214 feat(activity): mark the minutes before a look at the watch as awake too
• 5a1501d0 feat(infinisleep): add a marks page with "Not asleep yet"

Plus the commits that write this list, which cannot list their own hash, and the odd formatting or gitignore commit not worth a line.

Upstream

Everything else, including getting started, the app and watch face lists, the code walkthrough and the flashing guides, is unchanged and documented in the upstream README and under doc/.

Licenses

Unchanged from upstream: GNU General Public License version 3 or, at your option, any later version. It integrates FreeRTOS (MIT), LVGL (MIT), NimBLE (Apache 2.0) and Jetbrains Mono (Apache 2.0). Credit for InfiniTime itself belongs upstream.

The work in this fork was done with Claude Code.