A couple external GPS options have appeared for the iphone/Touch/Ipad. This would allow you to continue to use, in the case of the iphone/touch, the device as back-up navigation, or moving map AFTER you have lost cell signal, as it will not acquire a fix without assistance of the cell network.

For the Ipad, this would allow you to use the non-3G version which does not have a built GPS. Its about the same money to just get the 3G vs. buy the external GPS, but the external one would allow usage on another device - like your iphone/touch, etc.

http://bad-elf.com/products/gps/



The guy is a pilot, and blogs about using it in the air using ForeFlight HD: http://bad-elf.com/2010/11/08/ipad-in-aviation/

There is also a bluetooth one, but it appears to not be compatible yet with all software.
http://www.amazon.com/GNS-5870-MFI-Bluetooth-iPhone/dp/B004289ZW0/ref=pd_ybh_3?pf_rd_p=280800601&pf_rd_s=center-2&pf_rd_t=1501&pf_rd_i=ybh&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=19DHGE2XQ53PTKPJTVER

I am on the verge of splurge for an ipad for similar reasons as others - keep the paper out of the way, but this little guy would also provide a back-up option should the unlikely happen, and my Garmin 696 take a dump, as its my only form of navigation (short of my pilotage skills).

Anyway, more gadetry options upon which to become more dependent I know, I know....

I have an Ipad with the built in GPS. It works real good as a chart viewer, not so hot as a moving map. If I turn it off, switch to a different program or put it down where it loses the GPS signal even for a second that's it, no more moving map. I was told on a different thread the Apple GPS chip is very basic and to save battery life is very low powered. At airplane speed and altitude it is not good enough to reacquire the GPS signal. I asked the guys at foreflight about it and they said wait for the major software upgrade from Apple that supposedly is going to allow multi-tasking. They also said there were some external GPS units in the works, at that point all should be good. They hoped. Looks like we might be halfway there. I wonder how Bad Elf's GPS works on an ipad with GPS.

Good question, but they say it works "seamlessly" on the iphone 3G, GS, and 4 who have the cellular augmented GPS, so...

Good question to ask though.

and here is the answer:

Hello! Thanks for contacting us.

The Bad Elf GPS works great with the iPad 3G. The iOS device will automatically use the best data from the location sources available, it's all transparent to the apps.

Many pilots (including the folks at ForeFlight) have reported issues with the internal GPS in the iPad 3G - such as the inability to get/maintain a GPS lock in the cockpit, usually at high speeds and/or when it cannot use 3G tower triangulation and assisted GPS. The Bad Elf GPS does not have these problems. A number of GA and corporate jet pilots are doing real-world testing so we should have a blog post on this topic soon.

Best regards,
-Brett

Awesome, thanks John.