PRO TREK's ability to combine the best that technology has to offer and innovative designs has made it the timepiece of choice for climbers, hikers, campers, and other outdoor enthusiasts. Now the PRT-B50 Series adds Bluetooth capabilities that enable data communication with a smartphone running the PRO TREK Connected app, for the ultimate in ease of use. The Quad Sensor system uses compact sensors that make it possible to pack compass, altitude/barometer, and temperature measurements, along with an accelerometer that keeps track of your step count, into a compactconfiguration. Calorie calculations use both step count and altitude information to take upgrades and downgrades into consideration, andcalories burned values are recorded by the app. The app automatically records altitude data measured by the watch and route information acquired by a smartphone's GPS, and you can manually plot altitude points along your route using a Trekking Log feature. You can also perform a watch button operation to record your current location in memory. Then after you move to a different place, a Location Indicator will point to the direction and display the distance back to the registered location. This makes it easy to determine the relationship between the two locations, which is an essential capability for outdoor activities.