So, you bought an iPod Touch or a Wi-Fi-only iPad. These gadgets are way cool devices but what if you want to use one of them for navigation on, say, a car trip?\n\tIt's not the maps that will be the problem; there are quite a few really good offline navigation products for iOS devices, such as Navigon North America and PDF Maps, which I reviewed a few weeks ago in my Gearhead column over on Network World.\n\tNope, the problem you're going to have is that you won't know where you are because the iPod Touch and the WiFi-only iPad don't have built-in GPS receivers.\n\tNow, if you'd bought a 3G capable iPad you\u2019d have GPS, even if you never added on a cellular data plan. Alas, that is not the case when it comes to Wi-Fi-only iOS devices, so if you want to know where you are you'll need to add a GPS receiver.\n\tThere aren't a lot of products in this market but today I have one I really like and which has what has to be the best name: Bad Elf GPS, manufactured and sold by Bad Elf LLC.\n\tThe Bad Elf GPS is a tiny gadget about the size of a quarter that plugs into the connector on your iOS device and just works. It's amazingly simple. It also has a USB connector on the edge so that you can charge your iDevice at the same time that you use GPS.\n\tWhen you plug in the Bad Elf GPS for the first time it launches iTunes to download the free Bad Elf app. The app loads, checks to make sure the satellite data is up to date, updates it if not, checks the device firmware and updates that if necessary. Now any iOS app looking for GPS data will work.\n\tThe performance of the Bad Elf GPS is great: Its lock time (the time to acquire a GPS fix) is 45 seconds or less (I the average under good conditions to be 10 to 15 seconds), provides 2.5 meter accuracy (conditions permitting) and if you're in a vehicle that's more interesting than a car, it will work at up to 60,000 feet vertically and at speeds up to 1,000 MPH.\n\tI recently took a car trip and used the Bad Elf with the Navigon app on a WiFi-only iPad 2 and it worked brilliantly! The Bad Elf is actually very sensitive \u2026 even more so than my other GPS-enabled devices, as it worked fine without a clear view of the sky.\n\tIf you really need GPS and you were cheap cost conscious when you purchased your iPod Touch or iPad the Bad Elf GPS at $99 is a reasonably priced solution.\n\tBut when you next buy, say, an iPad (which will probably be next spring when it appears Apple will launch the iPad 3) go for the 3G version \u2026 for the current iPad 2 the 3G version with GPS the price difference is only $130 so while you'd spend a little more you wouldn't have an external device messing up the ultra clean\u00a0Apple design.\n\tEven so, the Bad Elf GPS is a great solution if you want to add GPS to an existing iOS device.\n\tYou can locate me on Twitter as @quistuipater, find me on Facebook as "quistuipater," and get a fix on me on LinkedIn as "Mark Gibbs."