Any good apps which allow you to download offline and preferably ordnance survey type maps? Going over the Alps through three different countries and it would be very useful to have offline maps available.
I know you can cache google maps but they seem to disappear after a while, and I don't know how good the maps would be for the side of a mountain.
Thanks in advance
There are plenty of apps that let you do this, the best route normally being to use Mobac (a desktop application -- no bad thing, since defining map areas on a phone screen is a huge ballache) to download the maps you want into an atlas package, and then copy this across to your phone's SD card or storage. You can point Mobac to all sorts of sources, including all the regular OSM styles as well as any custom tile server (so for example I have a custom style that is high-contrast so it's clear in bright sun). Naturally if you want "non-free" maps they, er, won't be free.
I use MyTrails, which (among other nice things) has a true offline map feature rather than just allowing its cache to be populated via Mobac.
Most of Europe doesn't have OS-type maps unfortunately.
[url=www.mapdroyd.com/]Mapdroyd[/url] lets you download and cache Openstreetmap maps for Europe and a lot of the rest of the world.
The maps aren't very detailed at all, and vector-based (so chances are if you try and use them for MTB you'll find yourself in the middle of a big expanse of grey or green, somewhere near a black line repsenting a road) but it's GPS compatible, accurate and free.
A leftfield option that might be worth considering:
https://play.google.com/store/apps/details?id=com.custommapsapp.android&feature=also_installed
For free mapping try installing Orux or similar and downloading maps from http://www.openandromaps.org/
You might want ot play about with the themes if it is for mountain biking as the singletrack stuff is not coloured well as its geared for main cycle routes. The volatile hiking theme works better but lacks cycle routes. A bonus is the files are incredibly small. Quality of mapping can vary greatly though from place to place.
Paid maps you could try some of the memory map stuff but I'm not sure how much mapping coverage is available outside the UK and france. My favourite mapping program for android is MMTracker which works excellently with older style memory map files if you can get hold of them.
Try Maverick Maps for Android, I've just used it for the same sort of trip as you. The open source Ski Maps are useful if you're in an area with coverage, eg all the bike parks.
Thanks a lot, plenty to look at. It is for mountain biking, and I realise most of the singletrack won't be marked but it would be good to have an idea of some off road routes in case we do get lost.
Another vote for maverick here. Used in NZ and it's surprising how much trail detail there is in some if the opensource mapping available. Very easy to use too.