Run your heart outforerunner 35 is slim and lightweight perfect for daily runs training and racing it features built in wrist based heart rate as well as gps that tracks your distance pace intervals and more and since all these stats are captured by the watch your watch is all you need no phone no chest strap just put on forerunner 35 and go stay connectedwhen paired with your compatible smartphone forerunner 35 offers the convenience of smart notifications right on your wrist alon