In reply to Stig:
ViewRanger is the one to go for.
Use either the freebie public domain mapping (OpenCycleMap) which has tracks, roads, and excellent/accurate detailed topo on it or else buy the 1:25k map tiles (pennies) as you need them.
I've used both types, both in UK and in Spain....both map-types are excellent but the 25k is my preferred option. ViewRanger on my iPhone provides just about everything the £400+ GPS systems do; tracking, planning, speeds, distance, time, pace, recording tracks, POIs, and loads more......explore the app and you will not be disappointed. Routes can be saved and/or uploaded (and you can download others' routes for free too). The app and the maps you buy are available on other platforms too (e.g. iPhone for use on the hill and iPad for planning and reviewing).
I used it recently for planning and executing a solo night crossing of Dartmoor and a friend of mine is currently using it as her main mapping system for Lands End - John O'Groats and she's definitely no navigator!
Only downside can be that GPS on iPhone (which I use) eats the battery, but (with practice and experimentation) I managed 10hrs and only used about 35% but had all the power hungry apps/capabilities switched off (no 3G, no WiFi, no Bluetooth, no data, screen brightness turned down) and made sure I touched the power switch to kill the screen as soon as I'd finished referring to it (the screen eats power). It looks like that the GPS seems to go into a low-consumption mode when you dab the power button, I may be wrong about that, but having 65% power remaining after 10hrs is good enough for me and better than I ever get using the phone with all capabilities switched on.
Take time to get to know it and you'll be delighted with what it can do.
Hope this helps.