CMF BY NOTHING D399

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CMF by Nothing Watch 3 Pro Smart Watch Instruction Manual

Model: D399

1. Setup

1.1 What's in the Box

  • CMF by Nothing Watch 3 Pro Smart Watch (Dark Grey)
  • Charging Cable
  • User Manual
  • Watch Band

1.2 Initial Charging

Before first use, fully charge your CMF Watch 3 Pro. Connect the provided charging cable to the watch's charging port and a compatible USB power adapter. The watch display will indicate charging status.

CMF Watch 3 Pro charging

Image: The CMF Watch 3 Pro in Dark Grey, showing the watch face and strap. This image illustrates the overall design of the smartwatch.

1.3 App Installation & Pairing

Download the Nothing X App 3.0 from your device's app store (Android 6.0+ or iOS 13+ required). Open the app and follow the on-screen instructions to pair your CMF Watch 3 Pro via Bluetooth. Ensure Bluetooth is enabled on your smartphone.

CMF Watch 3 Pro app pairing

Image: A close-up of the CMF Watch 3 Pro's display showing app icons, indicating the user interface for app selection and interaction.

2. Operating Instructions

2.1 Basic Navigation

  • Touchscreen: Swipe left/right, up/down to navigate menus and widgets. Tap to select.
  • Side Button: Press to wake the screen, return to the watch face, or access the app list.
  • Gesture Control: Utilize new gesture controls for one-handed operation (e.g., answering calls, controlling music).

2.2 Bluetooth Calling

The CMF Watch 3 Pro supports crystal-clear Bluetooth calls with AI noise reduction. You can make and receive calls directly from your wrist. Sync up to 30 contacts for instant access.

CMF Watch 3 Pro Bluetooth call

Image: A side view of the CMF Watch 3 Pro, highlighting its sleek profile and the side button. This view emphasizes the physical design of the smartwatch.

2.3 Health Monitoring

The watch features advanced 4-channel heart rate tracking, precise sleep monitoring (with sleep zone tracking), stress level monitoring, and SpO₂ level measurement. Access these features via the watch's menu or the Nothing X App.

2.4 Sport Modes & GPS

Select from over 130 sport modes. The watch features L1+L5 Dual Band GPS for ultra-accurate navigation during outdoor activities. Performance analysis is powered by GOMORE technology.

CMF Watch 3 Pro GPS tracking

Image: A person wearing the CMF Watch 3 Pro on their wrist, actively using the GPS tracking feature during an outdoor activity. The watch face displays navigation data.

3. Key Features

  • 1.43” AMOLED Display: Vibrant display with sharp resolution and up to 10% more screen area.
  • AI Energy Score: Tracks daily wellness by combining sleep, activity, and recovery data.
  • 150+ AOD Watch Faces: Extensive customization options for the Always-on Display.
  • IP68 Water Resistance: Protected against sweat and water splashes.
  • 13-Day Battery Life: Long-lasting battery for extended use.
  • Smart Movement Algorithm: Tracks workouts in detail, including aerobic/anaerobic performance, training load, and recovery time.
  • Compatibility: Seamlessly syncs with Apple Health, Google Fit, and Strava.
CMF Watch 3 Pro display and features

Image: A collage showcasing various features of the CMF Watch 3 Pro, including its AMOLED display, multiple watch faces, long battery life, and Bluetooth calling capabilities.

4. Maintenance

4.1 Cleaning the Watch

Wipe the watch screen and strap regularly with a soft, damp cloth. Avoid using harsh chemicals or abrasive materials that could damage the device.

4.2 Charging Best Practices

Use only the provided charging cable. Avoid exposing the charging port to moisture. Ensure the watch is dry before charging.

4.3 Strap Replacement

The watch strap features quick-release pins for easy replacement. Gently slide the pin to detach the strap and attach a new one.

5. Troubleshooting

5.1 Watch Not Turning On

Ensure the watch is fully charged. If the issue persists, try performing a soft reset by pressing and holding the side button for 10-15 seconds.

5.2 Pairing Issues

Check that Bluetooth is enabled on your smartphone and the watch. Ensure the Nothing X App is updated to the latest version. Try restarting both devices.

5.3 Inaccurate Health Data

Ensure the watch is worn snugly on your wrist, not too tight or too loose. Clean the sensor on the back of the watch. Update the Nothing X App and watch firmware.

6. Specifications

FeatureDetail
Model NumberD399
Display Size1.43 Inches
Display TechnologyAMOLED
Water ResistanceIP68
Battery LifeUp to 13 days
ConnectivityBluetooth
GPSL1+L5 Dual Band GPS
Operating SystemROTS
Item Weight1.8 ounces (51 Grams)
ManufacturerCMF BY NOTHING

7. Warranty & Support

For warranty information and support, please refer to the official CMF BY NOTHING website or contact their customer service directly. Protection plans are available for purchase separately.

  • 2-Year Protection Plan
  • 3-Year Protection Plan

Official Product Videos

CMF Watch 3 Pro by Nothing

Video: An official seller video showcasing the CMF Watch 3 Pro by Nothing, highlighting its design and key features.

© 2025 CMF BY NOTHING. All rights reserved.

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