One of the first to take advantage is Latitudie, which claims to be the first Google Latitude client for i Phone and i Pad.
Latitude, of course, is Google's social location service, which lets you share your location with friends and family from your device.
The developer claims that this saves on battery life, since it's not constantly updating.
The problem I've always had with Latitude is I'm not sure what it's for - other social location apps like Foursquare at least relate your location to a place - a bar or venue - so you can find friends, rather than just tracking you on a map.
That feature allowed you to click a button on Google’s homepage and access the i Phone’s location services.So long story short, I want to update the marker on the map using sensor data only and I cannot find a library function in the API that allows me to update latitude/longitude on the map.