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Assisted GPS (A-GPS)

The M400 has built-in GPS that provides accurate speed and distance measurement for a range of outdoor sports, and allows you to see your route on map in the Flow app and web service after your session.

M400 uses AssistNow® Offline service to acquire a fast satellite fix. The AssistNow Offline service provides A-GPS data that tells your M400 the predicted positions of the GPS satellites. This way the M400 knows where to search for the satellites and thus is able to acquire signals from them within seconds, even under difficult signal conditions.

The A-GPS data updates once a day. The latest A-GPS data file is automatically updated to your M400 when you sync your M400 with the Flow web service via FlowSync software or with the Flow app.

A-GPS Expiry Date

The A-GPS data file is valid for up to 14 days. Positioning accuracy is relatively high during the first three days, and progressively decreases during the 10th-14th days. Regular updates help to ensure a high level of positioning accuracy.

You can check the expiry date for the current A-GPS data file from your M400. In M400, go to Settings > General settings > About your product > A-GPS exp. date. If the data file has expired, sync your M400 with the Flow web service via FlowSync software or with the Flow app to update A-GPS data.

Once the A-GPS data file has expired, more time may be required for acquiring the current position.

GPS Features

M400 includes the following GPS features:

  • Altitude, ascent and descent: Real-time altitude measurement, as well as ascended and descended meters/feet.
  • Distance: Accurate distance during and after your session.
  • Speed/Pace: Accurate speed/pace information during and after your session.
  • Running index: In M400, Running Index is based on heart rate and speed data measured during the run. It gives information about your performance level, both aerobic fitness and running economy.
  • Back to start: Directs you to your starting point in the shortest distance possible, as well as shows the distance to your starting point. Now you can check out more adventurous routes and explore them safely, knowing that you're only a touch of a button away from seeing the direction to where you started.

For best GPS performance, wear M400 on your wrist with the display facing up. Due to the location of the GPS antenna on the M400, it is not recommended to wear it with the display on the underside of your wrist. When wearing it on the handlebars of a bike, make sure the display is facing up.