Features: GPS signal auto correct; One key switch(positive and negative); Bluetooth V4.0 heart rate monitor compatible with IPHONE 4S and above version IPAD 3 and above version supports multiple app; 3D pedometer; Compass; StopWatch timer(1/100s); Countdown; Three groups of alarm set; 3-GPS model; Three sport mode; Auto DST; Hourly chime function; 12/24 hour time format; Calendar week display; Auto global time zone setting; Second time/zebra time function; Manage/export motion trail calorie calculation upload pictures by setting time; Historical records and the query; User information set; Energy saving function; Power indicator; Perpetual calendar; 50m depth water resistant.