Because of this, John is moving to the OS app and showed us how his early exploration has proved very positive with planning routes and displaying them on screen, including an impressive "flyover" feature to view your route as you would walk (or cycle) it. The app give access to the OS maps - 1:25,000 and 1:50,000 that you'd use for these activities plus larger scale ones.
Here are two useful links:
Sign in for OS Maps
At the end of the presentation, Graham Bone showed us a fascinating site where you can overlay historic maps onto any area to see what it used to be like. (Link will appear here soon).