Originally Posted by Hannah on 'Rita T'
Is the GPS in an iPad
dependent on wireless or cell service
? For instance, will it work offshore
The GPS in the iPad is a full proper kosher as good as anyone else GPS. What makes it *better* is the cell service.
A normal GPS chip set can take minutes to get a lock i.e. calculate its position if it has been off for a while or has been moved whilst off or fully reset. This is becuase it has no idea where the satellites are (their ephemeris) and to download this data is has to scan through the available satellite identifiers to see which ones are visible.
The cell triangulation built into the iPad tells the system where it is to within a few hundred meters. This gives a kick start to the gathering of data needed to obtain lock, so when the iPad is in cell coverage it will be faster to give you position data, when not in coverage it will still be as fast as a standalone GPS.