Garmin Forerunner 225

With a heart rate monitor on the wrist, this tracker shows your current zone based on colors. Grey shows you are warming up, through to red that indicates that you are working at maximum effort. The use of colored zones makes it easy to monitor your heart rate at a glance while mid running, and as it uses an optical wrist sensor, you can be assured it is getting the most accurate reading possible. Similar to other Forerunners, the 225 has inbuilt GPS and an activity tracker to keep you up to date throughout your daily routine, and with an average 4 week battery life it’s an easily rechargeable tracker.