May be of limited use out in the sticks as you only get the map and not the satelite view but may be good to fall back on for a GPS location. It gives you a 10 mile radius.

http://googleblog.blogspot.com/2011/07/download-map-area-added-to-labs-in.html

Try ‘rmaps’ on Android – you can access OS maps amongst others which are cached, then available if your phone is in Airplane mode.

The cached maps in Google Maps are fine for cities, I used them in Amsterdam to avoid data charges since you can use the phone in ‘Airplane’ mode with GPS on.
For off road stuff they are a bit crap, Google Maps doesn’t show footpaths so you are better off with one of the OS Apps knocking about.

Personally I wouldn’t rely on a digital map.

I did find an app that will give me a simple OS grid reference from a GPS signal which will no doubt come in handy though. Wouldn’t be the first time i’ve been lost and not 100% sure where i am on the map!

Doesn’t rmaps require caching on a computer first though and then transfering?

That is really good – Android users have been crying out for the ability to cache maps for ages.

Android users have been crying out for the ability to cache maps for ages.

Mapdroyd does this for OpenStreetMap maps, you can have all of Europe on your phone if you like. Doesn’t have any navigation (beyond showing you your location) and not a terrific amount of use for off road though.