There is AirCub on Android. Its free.
Its basic vector mapping but it gives you the airspace your in and warnings if you breach airspace. The maps are upto date too. Uncluttered and clear. Pinch zoom is neat.
You just install it off the Android market and it works. It auto down loads the UK maps. Search for aircub on the android market. There is no fiddling about. I have found it very useful.
On the paragliding forums it saying it works well on cheap £70 phones as well as more powerful tablets
Its not fancy but it does a great job of avoiding air space infringements.
AirCub - (I don't think you can down load it from the website)