If you experience Bluetooth connection problems with the Sports mobile app using the Suunto Smart Sensor heart rate belt, make sure that the belt is tightly secured around your chest and is well moisturized with water. Then try the following steps:

  1. Turn off Bluetooth on your phone and switch the phone to airplane mode
  2. Wait for about 10-15 seconds
  3. Switch off from airplane mode and turn on Bluetooth
  4. Try to connect again with the app

If this doesn't work try again after restarting the iPhone.