Colmi R02 setup guide: how to use it and read your data

What's in the Colmi R02 box

The Colmi R02 packaging is minimal. Inside you'll find:

• •The ring in the size you ordered.
• •The magnetic charger: a small disc with a magnet that attaches to the flat side of the ring.
• •USB-A cable (some bundles include USB-C; the power adapter is not included, any standard USB charger works).
• •Quick-start booklet in multiple languages (content is very basic; for full details it defers to the app).
• •Sizing kit (if you ordered it), to find the right fit before committing to the actual ring.

How to wear the Colmi R02 correctly

Which finger: the Colmi R02 works best on the ring finger or middle finger of your non-dominant hand. These fingers have consistent blood flow and are less exposed to sudden movements during the day. Avoid the index finger (too much movement) and the pinky (often less consistent circulation).

Orientation: the side with the optical sensor (the flat or slightly curved inner surface of the ring) should sit on the underside of your finger, the side facing your palm. This ensures direct contact between the sensor and your skin. If the ring has a small dot or groove as a position indicator, place that on the underside.

Charging: how long the battery lasts and how to charge

With continuous monitoring active (heart rate, overnight SpO2, steps), the Colmi R02 typically lasts 5-7 days. With aggressive continuous overnight SpO2 monitoring it can drop to 3-4 days.

• •How to charge: attach the magnetic charger to the flat side of the ring. The magnet holds it in place. Connect the cable to any standard USB adapter (5V/1A is enough, no fast charger needed).
• •How to know it's charging: most R02 models show an LED that blinks during charging. When the LED turns off or stops blinking, charging is complete.
• •Full charge time: approximately 1-2 hours from empty.
• •Recommended routine: charge every 4-5 days in the morning during your shower or over breakfast. This way you never risk running out of battery overnight, when your data matters most.

First sync with FitMesh Sync: step by step

FitMesh Sync connects to the Colmi R02 over direct Bluetooth, without going through the manufacturer's companion app. You don't need to download the Colmi companion app to use FitMesh: you can keep it installed if you prefer, but it is not required.

1. Install FitMesh Sync: if you haven't already, download it from the Google Play Store. The beta version is accessible via an invite link from the /en/beta page.
2. Open FitMesh and go to "Devices": from the main screen, select the devices menu or tap the "+" button to add a new device.
3. Select "Smart ring" then "Colmi R02/R03": FitMesh starts a Bluetooth scan. Make sure your phone's Bluetooth is on and the ring is nearby (within 50 cm).
4. Pair the ring: when the Colmi R02 appears in the detected devices list, select it. Pairing takes a few seconds. No PIN is required.
5. First data sync: after pairing, FitMesh automatically downloads the historical data stored in the ring's memory (typically the past 7 days). This first sync can take anywhere from 30 seconds to a few minutes.
6. Subsequent syncs: future syncs happen automatically every time the ring is in range of your phone. You don't need to do anything manually.

For the full technical details on how the Bluetooth connection works, what happens during a sync, and how data fusion with your smartwatch is handled, read the full Colmi ring guide.

iPhone and Apple Health: what happens once you're set up

The Bluetooth connection between FitMesh Sync and the Colmi ring happens on Android, where the data is collected and uploaded to your FitMesh account. Once the data is in your account, however, you can access it anywhere: the FitMesh app for iPhone (iOS) and the Apple Health bridge are coming soon.

Understanding the data in the FitMesh dashboard

Once synced, the FitMesh dashboard shows your Colmi ring metrics organized by type.

Daily data

• •Steps and distance
• •Estimated calories
• •Active minutes
• •Average heart rate and resting heart rate

Overnight data

Available each morning after the first sync:

• •Total sleep hours
• •Sleep stage breakdown (light, deep, REM, awake)
• •Overnight HRV (heart rate variability)
• •Overnight SpO2 (estimated oxygen saturation)
• •Overnight minimum heart rate (resting HR)

Unified view with your smartwatch

If you have already connected a smartwatch to FitMesh (Galaxy Watch, Pixel Watch, Garmin, Amazfit, and others), the Colmi ring data integrates automatically with watch data on the same timeline. At night the metrics come from the ring; workout sessions and daytime metrics come from the watch. There is no double counting.