Generate a shit load of random geocoordinates around a given distance.

gistfile1.m

#define RADIANS_TO_DEGREES(radians) ((radians) * (180.0 / M_PI))
#define DEGREES_TO_RADIANS(angle) ((angle) / 180.0 * M_PI)

#define ARC4RANDOM_MAX 0x100000000

double startingLatitude = DEGREES_TO_RADIANS(39.753638);
double startingLongitude = DEGREES_TO_RADIANS(-105.007375);

double earthRadius = 3960.056052;
double maxdist = 50.0f;

maxdist = maxdist / earthRadius;

for (int i = 0 ; i<100 ; i++)
{
    double random1 = ((double)arc4random() / ARC4RANDOM_MAX);
    double random2 = ((double)arc4random() / ARC4RANDOM_MAX);

    double randomDistance = acos(random1 *(cos(maxdist) - 1) + 1);
    double brg = 2 * M_PI * random2;

    double lat = asin(sin(startingLatitude) * cos(randomDistance) + cos(startingLatitude) * sin(randomDistance) * cos(brg));

    double lon = startingLongitude + atan2(sin(brg) * sin(randomDistance) * cos(startingLatitude), cos(randomDistance) - sin(startingLatitude) * sin(lat));

    if (lon < (M_PI * - 1))
    {
    lon = lon + 2 * M_PI;
    }

    if (lon > M_PI)
    {
    lon = lon - 2 * M_PI;
    }

    CLLocationCoordinate2D coord;
    coord.latitude = RADIANS_TO_DEGREES(lat);
    coord.longitude = RADIANS_TO_DEGREES(lon);
}

Have used this multiple times! Thanks for sharing!