Choose a finger that offers a snug, comfortable fit—neither too tight nor too loose. Since finger size and shape vary, try different fingers to find the most secure placement for accurate SpO2 and heart rate tracking.

O2Ring could fit most size of adults' finger, if thumb is too skinny, MiniRing maybe a better choice.

The device has built-in storage, it is not necessary to open App.You can open app to change some settings of device.

Generally speaking, yes. However, frequently movement may make the readings unavailable.Usually, the readings will recover in a few seconds after stop moving.

Wear the device on your finger, it will power on automatically. If can’t power on, charge you device first.

Take the device off your finger, it will power off automatically in a while if not connected to App.

Yes, you can set the screen mode in App. Battery will runs out a bit faster in the Always On Mode.

Touch the key on the top of device, you can wake up the screen. You can also check time and battery with the touch key.

Simply touch the button on top of the device to switch the display from time to oxygen level and pulse rate.

There are 3 brightness levels – Darkest, Medium, Brightest – so you can adjust the display for both daytime and nighttime use.

1. Sync via App (Recommended)

Device time will automatically sync with your phone’s time once connected to the ViHealth App.

2. Sync via PC Software

If needed, you can also sync the time manually using the PC software “O2 Insight Pro”:

1) Download the software: https://getwellue.com/pages/pc-software

2) Connect your O2Ring to the PC using the supplied black USB cable

3) Launch O2 Insight Pro

4) Click “Configure” → “Synchronize the clock” → “Save”.

The O2Ring measures SpO2 continuously—once every second —to ensure accurate real-time tracking, especially during sleep or activity.

This frequency is preset for medical-grade monitoring and cannot be modified manually, as it’s optimized for both accuracy and battery performance.

If you’re using the ring overnight or for spot checks, there’s no need to adjust the sampling rate—it’s always working in the background.

The device can store last 4 sessions, up to 10 hours for each.

1) While it’s charging, press and hold the circular button for about 10 seconds until the screen turns off.

2) Unplug the charging cable — the device will automatically restart.

If you need further help, feel free to contact us at support@getwellue.com.

Take off the device. After the countdown, the data will be ready for sync. 

1) After the countdown, open App to sync data. 

2) Or next time after you turn on your device, open App to sync. 

If measurement time is less than 2 minute, there will be no data.

This usually means the ring is still connected to another device (like your iPhone). Here's how to fix it:

1) Turn off Bluetooth on any other phone or tablet that may have previously connected to the ring. Force close the ViHealth app on those devices.

2) Then, on your phone, restart the ViHealth app and try connecting again.

💡 The O2Ring can only connect to one device at a time. Disconnecting from others first will solve most pairing issues.

1) Open the ViHealth app and tap on the record you want to share.

2) Tap the Share icon in the top right corner of the report screen.

3) Choose PDF as the format, then tap Share. Use your phone’s share options to send the file via email, message, AirDrop, etc.

The PDF includes your full overnight graph, oxygen drops, pulse rate range, and summary — useful for sharing with your doctor or saving for personal records.

This may happen if the ring was worn too loosely or too tightly, which can prevent the sensor from continuously detecting valid data. We recommend trying it again for another night and making sure the ring fits snugly but comfortably on your finger.

If the issue continues, please contact us at support@getwellue.com with:

1) A photo or short video showing how the ring is worn

2) A screenshot of the data gap or missing records on the app

3) Your order number or the email address used at checkout

We're happy to help!

Yes.

No, you won’t lose any data. As long as you upload each session after use, your records will be saved in the “Blood Oxygen History” section of the ViHealth app.

You can safely switch between devices — the app keeps data from each one separately and securely, even after several days.

Each record in the ViHealth app includes the data source name at the bottom of the [Details] page.

If you have two of the same model (e.g., two O2Rings), the last four digits of the device serial number (SN) are shown in the name.

You can use these to distinguish between devices and keep your data organized.

DO NOT PAIR in the system settings of your phone. Make sure the Bluetooth is enabled on your phone and device’s battery is not out.

With android phone, you need to allow Location access to make Bluetooth work. We DO NOT collect your location data.If you have refused the permission, you can try following steps to allow the access: 

1) Reboot your phone; 

2) Turn on “location”on your phone; 

3) System settings -> Apps-> ViHealth, allow location access.

Yes.

This means the Ring is still trying to stay connected to your phone. To turn it off, simply turn off Bluetooth on your phone and close the ViHealth app. The O2Ring will automatically shut down after a short time.

Yes. Once connected, you can go to the O2 Reminder section to turn vibration on/off and set thresholds. Vibration intensity can be adjusted separately.

O2 Reminder

Adjust threshold (80–95%) in 1% steps.

PR Reminder

Low PR threshold: 40–70 bpm, in 5 bpm steps.

High PR threshold: 90–200 bpm, in 5 bpm steps.

Offline Reminder

- After the switch is turned on, if the device becomes offline on Dashboard, the phone will sound an alarm and vibrate immediately.

- Device Offline Reminder works only when you stay in Dashboard and keep the screen awake.

-The reminder sound follows your phone’s system volume settings.

Device Vibration Intensity

5 vibration levels for reminders: Very Weak, Weak, Medium, Strong, Very Strong.

Yes, we understand how frustrating that can be, especially if you're already a light sleeper. Here are a few ways to reduce disruptions while still getting valuable data:

1) Turn off or adjust the vibration alert:

In the ViHealth app, you can either turn it off or set a lower threshold (e.g. SpO₂ < 85%) so it only triggers for more serious drops.

2) Use daytime monitoring:

If overnight use is disruptive, consider wearing the O2Ring during daytime naps or while relaxing in the evening — it still captures useful trends.

3) Review the data instead of real-time alerts:

You can disable alerts entirely and simply check the detailed report in the morning, which includes every desaturation and event without waking you up.

If you'd like help adjusting your settings, please refer to the detailed steps in the previous question: “How to Set Up SpO2/PR Reminder.”

Yes. After syncing your data to the app, you can view vibration triggers on the graph. Each small orange triangle (▲) marks a vibration alert, showing when the alarm was activated in response to low oxygen levels or abnormal pulse rate.

This is likely caused by the Offline Reminder feature being triggered. Here's how it works:

If this setting is turned on, your phone will immediately sound an alarm and vibrate when the ring goes offline (e.g., due to Bluetooth disconnection).

To turn this feature off:

If the issue persists, please contact us at support@getwellue.com with a short description of the problem. If possible, include a photo or brief video showing the issue.

To help us assist or arrange a replacement if needed, please also include your order number or the email address you used at checkout. We're happy to help!

The vibration alert follows a smart cycle and cannot be set manually. Here's how it works:

- Each alert lasts up to 40 seconds, starting with light vibrations and gradually becoming stronger.

- If your oxygen or heart rate returns to normal during the cycle, the vibration will stop immediately. Once it stops, there is a 20-second pause before a new alert can be triggered.

- If abnormal readings continue without interruption, the device will start a new 40-second vibration cycle—from light to strong—repeating this process until the readings normalize.

While you can't set a custom duration, you can adjust the alert thresholds and turn the vibration on/off in the ViHealth app settings.

There are a few ways to control or disable vibration, depending on what you want:

Device vs. App Alerts:

The O2Ring and the ViHealth app have separate alert settings. You can turn one off while keeping the other on.

- Temporarily silence device vibration:

Just tap the touch key on the O2Ring when it vibrates. This stops the vibration for the moment, and it won’t trigger again for the next 20 seconds.

- Turn off app alerts:

In the ViHealth app, tap the alarm bell icon on the Dashboard screen to disable app-based alerts.

I don’t want any alerts — even if my oxygen is low. How can I turn them off completely?

Turn off device vibration alerts:

In the ViHealth app, go to Settings, and turn off them:

O2 Reminder

PR Reminder

You can re-enable any of these settings at any time.

Yes — while the O2Ring doesn’t diagnose sleep apnea, it acts as a powerful screening tool.

It continuously tracks your oxygen saturation (SpO2) and pulse rate every second throughout the night. If you have sleep apnea, your breathing may pause repeatedly during sleep, causing oxygen levels to dip and heart rate to spike — and the O2Ring detects those patterns clearly.

- Oxygen drops below 90% can signal possible apnea events

- Heart rate spikes often follow breathing interruptions

- Real-time alerts and trend graphs make it easy to spot unusual patterns

It refers to the average blood oxygen saturation (SpO2) throughout the session. A healthy range is typically above 95%.

This is the average heart rate per minute during the session. Normal resting rates range between 60–100 bpm, though athletes and some users may have lower averages.

It detects physical movement during the session — useful to assess whether changes in oxygen or heart rate were linked to body movements.

02 Score is a measure of oxygen shortage during whole sleep. It combines frequency, duration, and depth of oxygen drops. A higher score means oxygen is richer; Lower score means oxygen is shorter. The score ranges from red (poor) to green (good).

For example, a score of 10 means no hypoxia.

Oxygen drops (or desaturation events) happen when your blood oxygen level falls temporarily — often during sleep or shallow breathing. While mild drops are normal, frequent or deep drops (especially below 90%) can signal issues like sleep apnea or lung problems.

Tracking them helps you spot early signs of breathing irregularities. In fact, the American Academy of Sleep Medicine (AASM) considers drops of ≥3% important for diagnosing sleep disorders, while Medicare uses a stricter ≥4% standard. Monitoring both ensures nothing gets missed.

These show how many times your oxygen level dropped by more than 4% from baseline, and how frequently this occurred per hour. 

The baseline refers to your average, stable oxygen level during a period of normal activity or rest, without significant fluctuations. For example, if your average oxygen level is 98%, a drop of more than 4% would mean your oxygen level drops below 94%.

The term “drops >4%” refers to oxygen level drops where your SpO₂ decreases by more than 4 percentage points—not 4% of a specific number. For example, if your oxygen level drops from 97% to 92%, that would count as a drop >4%. It’s an absolute difference, not a percentage of your original number.

This information is important for detecting breathing irregularities, such as sleep apnea, where oxygen levels can drop suddenly and repeatedly throughout the night. For instance, if your oxygen level drops below 94% multiple times per hour, it may indicate irregular breathing patterns that require attention.

Same as above, but for drops over 3%. Useful for detecting lighter but still significant fluctuations.

The American Academy of Sleep Medicine (AASM) is the leading professional society for sleep medicine in the U.S. It sets widely accepted clinical guidelines for diagnosing sleep disorders, including sleep apnea. AASM recommends scoring hypopneas when oxygen saturation drops by ≥3% or when there is an arousal from sleep.

The Centers for Medicare & Medicaid Services (CMS), known as Medicare, is the U.S. federal agency that manages health coverage for seniors and others. It uses a ≥4% oxygen drop criterion for scoring hypopneas when determining insurance coverage for sleep apnea treatment.

By tracking both thresholds, devices like O2Ring align with both medical and insurance standards — helping users and doctors make informed decisions without missing important signs.

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No, the number of 4% drops and 3% drops are not mutually exclusive. A 4% drop is a subset of 3% drops. This means if a drop qualifies as a 4% desaturation, it’s already included in the count of 3% drops. Therefore, you should not add the two together to calculate a total, as this would result in double-counting some events.

ODI stands for Oxygen Desaturation Index, which measures how many times your blood oxygen level drops by more than 3% and 4% during a specific period.

ODI 3% counts how many times your SpO₂ drops more than 3% from your baseline within a certain time period, typically per hour.

ODI 4% tracks how many times your SpO₂ drops more than 4% from the baseline during the same period.

The higher the ODI value, the more frequent the drops in oxygen levels, which may suggest potential issues that could require medical attention.

This shows the lowest and highest oxygen saturation recorded during the session.

This is the full range of your heart rate throughout the session.

It breaks down the time you spent in different oxygen level ranges:

95%–100%: Normal

90%–94%: Slightly low

<90%: Concerning — prolonged time here may signal a health issue.

This indicates how long your heart rate stayed in each range. A high percentage below 50 bpm during sleep can be normal for some, but if paired with symptoms, consult a doctor.

Use the “Add notes” section at the bottom of the report to log relevant symptoms or behaviors (e.g., coughing, CPAP usage).

PI" stands for Perfusion Index — a number that reflects the strength of blood flow at the sensor site (like your finger). It’s calculated from the pulse signal and is usually expressed as a percentage.

A higher PI means stronger blood flow, which can indicate better signal quality. Most people see values between 0.2% and 20%, depending on factors like temperature, movement, or circulation.

Why it matters:

- Low PI? Cold fingers, poor circulation, or loose fit might be affecting your signal. Try warming your hand or adjusting the ring.

- High PI? Good blood flow — your readings are more reliable.

- During sleep: Tracking PI changes may help you notice circulation issues or movement disturbances overnight.

Example: If your SpO₂ graph looks unstable or the app can’t detect your pulse, check the PI value — a low PI (<0.5%) often explains weak signals.

Please be assured that all Wellue products provide medically accurately measurement.

Different manufacturers utilize algorithms with different average SpO2 times, which is a significant element when calculating the reading. The shorter the collecting duration, the more sensitive the result, the fast the response. Oxygen monitor with too long assessment time is not the best choice for oxygen saturation detection, especially during sleep. Wellue’s intelligent averaging algorithm collects data quickly and identifies the precise SpO2 value. 

Therefore, it is not rigorous to compare oxygen monitors that utilize different averaging algorithms.The comparing result will be much more accurate if obtained by an arterial blood gas.

It’s normal to see a small difference—typically 2% to 5%—between the O2Ring and other oximeters, especially hospital fingertip models. That’s because:

- Different measurement positions: The O2Ring measures oxygen at the base or middle of your finger, while fingertip devices read at the tip. Blood flow and tissue thickness vary in each location.

- Different sensor technology and algorithms: Medical offices may use devices calibrated differently. The O2Ring is designed for continuous, overnight monitoring and uses proprietary algorithms to filter movement and noise.

- Circulation and temperature: Cold fingers, loose placement, or poor circulation can affect any pulse oximeter’s accuracy.

No manual calibration needed: The O2Ring is pre-calibrated. It does not support offset adjustments, but it reliably tracks real-time oxygen trends.

For best results, wear the ring snugly, keep your hands warm, and stay still during readings. While the O2Ring is excellent for daily monitoring and sleep tracking, always consult your physician for clinical diagnosis.

1) Please ensure that the battery has sufficient charge.

2) If the issue is not related to low battery, please record a short video showing what happens after you put the ring on.

Then, contact us at support@getwellue.com with a brief description of the problem.

To help us assist or arrange a replacement if needed, please also include your order number or the email address you used at checkout. We're happy to help!

If you can’t connect your device after updating iOS, please try the following steps: 

1) In the system settings, turn off and turn on Bluetooth; 

2) In the Control Center, tap the Bluetooth icon repeatedly to re-enable Bluetooth. 

Turn on device, run App to connect it.

The O2Ring is made from medical-grade silicone that is both durable and comfortable for long-term wear. The material that directly touches your skin is silicone, which is hypoallergenic and gentle, ensuring it’s safe for most skin types. 

The O2Ring band may naturally wear out or break after extended use. If this happens within the 1-year warranty period, we’ll be happy to replace it for you at no charge.

Please contact our support team at support@getwellue.com with your order number or the email address used at checkout, along with a photo of the issue.

The O2Ring has an IP22 rating, which means it is water-resistant to light splashes and sweat, but it is not waterproof. It is not recommended to wear it while swimming or submerging it in water.

The O2Ring is designed to fit finger circumferences between 55.24 mm – 65.53 mm (approximately 2.17" – 2.58").

This is usually due to using an outdated version of the ViHealth app. We regularly update the app with new features, so it’s important to:

1) Go to the App Store or Google Play and update ViHealth to the latest version.

2) After updating, reconnect your device and check the settings menu to see if the feature is available.

Still not seeing it? Feel free to contact us at support@getwellue.com—we’re happy to help!

1) Open the ViHealth app. Tap the Profile icon in the bottom right corner.

2) Tap the third option, “Language,” then select your preferred language from the list.

To ensure accurate data attribution, follow these steps before each use:

1) Open the ViHealth app. Tap the top-left avatar icon on the main screen.

2) Select “Members” and choose the correct user profile. If the other person is not listed, tap “Add User” and create a new profile.

💡 Always switch to the correct user before wearing the ring. This ensures the data is saved under the right person’s profile.