The T-Rex is technically a smartwatch but has the makings of a fitness band. So, it counts steps, calculates calories burnt, and covers all the basic sports modes (14 in total) including run, treadmill, outdoor, cycle, and triathlon, among others. It also has a built-in GPS and a 24-hour heart rate monitoring. The GPS takes around 15 seconds to lock the location, but is fairly accurate. Beyond that, the watch uses PPG Bio-Tracking Optical Sensor to track heart-rate, although it takes its own sweet time to get to the result. It also tracks sleep. The sleep analysis feature breaks down the user's sleeping hours into light sleep, deep sleep, and awake. Moreover, it also gives a sleep quality score and a comparison with other users.