How to use iPhone4 for gps/mapping

[AmyL]

I spent a ton of time figuring out how to use an iPhone4 as my gps/mapping tool for backpacking.  I learned a bunch of things that are equally important for bikepacking too.  Both users have requirements that most users of iphone mapping apps don't care about:  battery life, types of topo maps, and use outside of WIFI/phone signal range.

Personally I chose an iPhone instead of a Garmin because it better met my requirements (long trips outside the US).  I didn't document the advantages and disadvantages of Garmin vs iPhone, but I did document how to make the iPhone work well, so if you have an iPhone4 and you want to try to use it as a GPS device, here's everything (I hope) you need to know:
http://adventurealan.com/iphone4gps.htm

AmyL, Palo Alto
amyl.smugmug.com

[Aslan]

Amy,

Thanks for the post.  I have been using my 3gs for 3-5 day bikepacking trips and creating and saving tracks.  I use this incredibly expensive $3 AA to USB battery bank to keep it topped up.

Portable AA Battery Powered Emergency Charger with Flashlight - Black - For Anything Powered Via USB
http://www.amazon.com/gp/product/B003M9Z5F6

The key thing with the batteries is to use the 8x lithium batteries as they will give almost 2 full charges.  Alkaline AA's only give you a 50% charge.  Lithium AA's are also much lighter.  Another issue is you want to avoid charging while actively recording a track as the system warnings of 'device not supported' override your GPS apps and interrupt your track recording.  It is not a problem as long as you top it up at the end of the day.