In addition to the GT-820, the Pro-HRM has the following
Heart rate monitor; Digital compass; Barometric altimeter; Larger 64MBit memory; 200,000 waypoints
i-gotU GT-820 series is a sophisticated GPS computer which is handy for many outdoor and sport activities. Its 1.4" back-lighted LCD display details all the essential GPS information you need to know on the go, including speed, distance, altitude, time, pace, heart rate, calories burned, and much more. This light weight GPS device can be portable or mounted onto your bike. It also supports the Bluetooth Low Energy wireless interface for connection with heart rate monitors for performance measurement. i-gotU GT-820 series is truly the best travel mate that bike riders, travellers, or photographers could ever have. Pairing with a cadence sensor will be available as a firmware update in September 2013.
Supports the following languages; English, French, German, Italian, Spanish, Dutch, Russian, Japanese, Traditional Chinese, Simplified Chinese