Outdoor sports watches are designed especially for outdoor and sports activities. They feature GPS and other functions useful for hiking and trekking, but also various sports activities, such as swimming, cycling or running. Sports watches also usually have a barometer, altimeter and a compass. More advanced watches can also measure your heart rate frequency; however, this is not a requirement, unlike with heart rate monitors. You can pick out high-quality sports watches from leading manufacturers Suunto, Polar, TomTom or Fitbit.