Case study

Daybreak: rebuilding COLMI R09 BLE communication for an offline ring client

Daybreak rebuilds COLMI R09 smart-ring communication in an offline Android client. Its Kotlin protocol module handles 16-byte commands and checksum validation, reassembles multi-packet sleep records, and processes heart-rate logs, steps and SpO2 data; the app computes local sleep, recovery and activity scores from the readings.

Targets: Protocol
Category: Independent reconstruction cases
Relationship: Independent reconstruction project
Sources reviewed: 2026-11-06
Evidence class: C2 code & docs, no demo or download

Stars: 0
Last commit: 2026-07-10
Language: Kotlin
License (GitHub): MIT

GitHub data as of 2026-11-10

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Evidence

Observed: Code, documentation and a demo observed; no download method found.
Checked: 2026-11-08

How evidence classes are assigned

Requirements & limits

Prerequisites: COLMI R09 smart ring and Android 8.0+ for the app.
Prerequisites: JDK 17+ and Android SDK to build.
Limits: The source notes firmware-dependent HRV and noisy sleep staging.
License: MIT license.

Cite

BibTeX

@misc{daybreak-colmi-r09-case,
  title = {{Daybreak: rebuilding COLMI R09 BLE communication for an offline ring client}},
  howpublished = {\url{https://github.com/reuhenbhalod/DayBreak}},
  url = {https://github.com/reuhenbhalod/DayBreak},
  urldate = {2026-11-06},
  note = {Awesome REA entry: \url{https://awesomerea.org/resources/daybreak-colmi-r09-case/}}
}

Plain text

Daybreak: rebuilding COLMI R09 BLE communication for an offline ring client. https://github.com/reuhenbhalod/DayBreak (accessed 2026-11-06). Awesome REA entry: https://awesomerea.org/resources/daybreak-colmi-r09-case/

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Primary sources

README.md GitHub · reuhenbhalod/DayBreak · Revision 21dd3e3