Wi-Fi Only iPad 2 Can Use iPhone’s GPS When Tethered
One of the downsides – although there aren’t many of them – to Apple’s new iPad 2 is that if you purchase one of the Wi-Fi only models, it doesn’t come equipped with a GPS chip to pinpoint your location. So, if you purchased a pricey navigation application to use as a big, beautiful sat-nav on your iPad, you’re not going to get accurate results unless you go for a 3G model. However, there is a workaround; it seems that when you tether your iPad 2 to your iPhone, you can use its GPS as well as its data connection.
The feature was discovered by Kyle Carmitchel on a recent road trip, who was tethering his iPad to his iPhone 4 using the new Personal Hotspot feature introduced in iOS 4.3. Carmitchel found that when the two devices were hooked up to each other, the iPhone was feeding its GPS data to the iPad:
It is clear I am being fed GPS information from the phone, at what appears to be an interval of once a minute or so between refreshes (likely they didn’t do real time updating so as to go easy on the phone’s battery).
Without a GPS chip, the iPad is still able to locate itself using Wi-Fi hotspots; by taking the MAC address of the router the it’s connected to and looking it up in a database of router locations, the iPad can come up with an approximate location, but it’s not at all very accurate. However, by gathering an iPhone’s location data over a Personal Hotspot connection, the iPad can take advantage of the same pinpoint GPS accuracy as the iPhone.
At present, it’s hard to say whether this is compatible with the original iPad, or any iPhone earlier than the forth-generation device, but if it works well, you could save yourself a few bucks on the iPad if you were planning to pay extra for the GPS chip. However, if the location data is only fed to the iPad once a minute as Carmitchel describes, it still may not be accurate enough for some navigational purposes.[via Cult of Mac]