1. Introduction and Overview
The COROS APEX 2 Pro is an advanced outdoor GPS watch engineered for durability and precision. It combines robust construction with comprehensive tracking features, making it an ideal companion for various outdoor activities and rigorous training. This manual provides essential information on setting up, operating, maintaining, and troubleshooting your device.

Figure 1: Front view of the COROS APEX 2 Pro GPS Watch.
Key Features:
- Extended Battery Life: Up to 30 days of regular use or 75 hours in full GPS tracking mode.
- Superior GPS Accuracy: Dual-frequency GPS and all-satellite GNSS chipset for precise data.
- On-Wrist Navigation: Downloadable global Landscape and regional Topo maps.
- Advanced Training Solutions: Insights on training load, recovery, and workout building.
- Accurate Heart Rate Monitoring: New 5-LED optical heart rate sensor with 4 photodetectors.
- Durable Design: Sapphire glass screen and grade 5 titanium alloy bezel for enhanced protection.
- Wide Activity Support: Includes Run, Bike, Swim, Ski, Mountain Climb, Strength, and more.
2. Setup and Initial Use
Follow these steps to set up your COROS APEX 2 Pro watch for the first time:
- Charge the Watch: Connect the charging cable to the watch and a USB power source. Ensure the watch is fully charged before first use.
- Download the COROS App: Install the official COROS app on your smartphone from your device's app store.
- Pair with Smartphone: Open the COROS app, create an account or log in, and follow the on-screen instructions to pair your watch via Bluetooth.
- Initial Configuration: The app will guide you through setting up personal information, time zone, and initial preferences.
- Update Firmware: Check for and install any available firmware updates through the COROS app to ensure optimal performance and access to the latest features.

Figure 2: The COROS APEX 2 Pro product packaging.
3. Operating Your COROS APEX 2 Pro
3.1. Battery Life Management
The APEX 2 Pro offers extended battery performance. To maximize battery life, ensure regular software updates and manage GPS modes according to your activity needs. The watch takes less than 2 hours to go from zero to full charge.

Figure 3: Battery life comparison between APEX 2 and APEX 2 Pro models.
3.2. GPS Accuracy and Navigation
The watch features a 50% higher performance antenna and an All-Satellite GNSS chipset, receiving signals from all five major satellite systems for highly precise data. The APEX 2 Pro also includes dual-frequency technology for enhanced accuracy.

Figure 4: Internal components related to GPS accuracy in COROS watches.
Utilize the downloadable global Landscape and regional Topo maps for on-wrist navigation. You can sync and follow routes created in the COROS app directly on your watch.

Figure 5: On-wrist navigation using global offline maps.
3.3. Heart Rate Monitoring
The new optical heart rate sensor features a 5-LED system with 4 photodetectors, providing advanced data accuracy for both daily tracking and activity monitoring.

Figure 6: Heart rate monitoring in action.
3.4. Activity Modes and Training Solutions
The COROS APEX 2 Pro supports a wide range of activity modes including Run, Bike, Swim, Ski, Mountain Climb, and Strength. Settings can be easily adjusted via the COROS app or directly on the watch.
Leverage advanced training solutions like training load trend, recovery timer, and workout builder to transform your data into actionable insights. The COROS app and Training Hub provide comprehensive tools for personalized training.

Figure 7: Creating training plans in the COROS Training Hub.

Figure 8: Tracking recovery and sleep quality with the COROS app.
3.5. Durability and Design
The watch is built with a sapphire glass screen and a grade 5 titanium alloy bezel, providing robust protection for the internal electronic components. The 1.3-inch Always-On Memory LCD Touch Sapphire Screen and PVD-coated bezel are scratch-resistant.

Figure 9: Design features emphasizing durability.
The APEX 2 Pro is 5 ATM water resistant, suitable for open water activities and capable of withstanding pressures up to a depth of 50m. It is also temperature resistant, operating in temperatures ranging from -20°C to 50°C.

Figure 10: Water resistance of the COROS APEX 2 Pro.

Figure 11: Temperature resistance from -20°C to 50°C.
3.6. Official Product Video
Video 1: Official COROS APEX 2/2 Pro overview, showcasing features and use in various outdoor environments.
4. Maintenance
Proper maintenance ensures the longevity and optimal performance of your COROS APEX 2 Pro watch:
- Cleaning: Regularly clean the watch and strap with a soft, damp cloth. Avoid harsh chemicals or abrasive materials.
- Charging: Use only the provided charging cable. Avoid exposing the charging contacts to excessive moisture or dirt.
- Software Updates: Periodically check for and install firmware updates via the COROS app to benefit from performance improvements and new features.
- Storage: When not in use for extended periods, store the watch in a cool, dry place.
5. Troubleshooting
If you encounter issues with your COROS APEX 2 Pro, consider the following common solutions:
- Watch Not Turning On: Ensure the watch is fully charged. If it still doesn't turn on, try a soft reset by holding down the digital dial and back button simultaneously for 15 seconds.
- GPS Signal Issues: Ensure you are in an open area with a clear view of the sky. Syncing with the COROS app before an activity can help update satellite data.
- Bluetooth Connectivity Problems: Ensure Bluetooth is enabled on your phone and watch. Try unpairing and re-pairing the device in the COROS app. Restarting both devices can also resolve connectivity issues.
- Inaccurate Heart Rate: Ensure the watch is worn snugly on your wrist, about one finger-width above the wrist bone. Clean the optical sensor regularly.
- Battery Draining Quickly: Reduce the frequency of GPS recording (e.g., from Every Second to Smart Recording), turn off unnecessary notifications, or reduce screen brightness.
For more detailed troubleshooting or persistent issues, refer to the official user guide or contact COROS customer support.
6. Specifications
| Feature | Detail |
|---|---|
| Brand | COROS |
| Model Number | W521 |
| Product Dimensions | 5 x 5 x 5 inches |
| Item Weight | 1.87 ounces (53 Grams) |
| Screen Size | 1.3 Inches |
| Display Type | Always-On Memory LCD Touch Sapphire Screen |
| Bezel Material | Grade 5 Titanium Alloy with PVD Coating |
| Water Resistance | 5 ATM (50 meters) |
| Battery Life (Regular Use) | 30 days |
| Battery Life (Full GPS) | 75 hours |
| GPS | Built-in GPS, Dual-Freq, All-Satellite GNSS |
| Heart Rate Sensor | New optical heart rate sensor (5-LED system, 4 photodetectors) |
| Memory Storage Capacity | 32 GB |
| Operating System | Self-developed embedded operating system |
| Connectivity Technology | Bluetooth |
7. What's in the Box
Upon opening your COROS APEX 2 Pro package, you should find the following items:
- COROS APEX 2 Pro Watch
- Watch Band
- Charging Cable
- Synopsis / Quick Start Guide
- Next-generation optical heart rate sensor (integrated)
- Free global offline landscape and topographical maps (downloadable)

Figure 12: Contents typically found in the COROS APEX 2 Pro packaging.
8. Warranty and Support
For detailed warranty information and customer support, please refer to the official COROS website or the comprehensive user guide provided in PDF format.
Official User Guide (PDF): Download Here
For further assistance, you may contact COROS customer support directly through their official channels.





