You are a developer and want to work with tracks and/or markers? Well, it's YOUR data, here is the format description!

Tracks:
Tracks are just a couple of database records, each representing one position and it's data (called a trackpoint). This is the structure used inside of cotoGPS:
typedef struct
{
	double lat, lon;
	double dist;
	double arc;
	double x, y;
	Int16 alt;
	UInt16 hdop;
	UInt16 vdop;
	UInt16 pdop;
	UInt8 sat_tracked;
	UInt8 fix_quality;
	UInt16 speed;
	UInt32 time;
} trackpoint_type;

element description:

Marker:
#define MAX_MARKER_NAME_LENGTH  20

typedef struct
{
	double lon, lat;
	Char name[MAX_MARKER_NAME_LENGTH];
} marker_type;

element description:

Have fun! :-)