In reply to GrahamD:
If you download the VieiwRanger GPS App (I'm sure other Apps will works as well) you can view on a smartphone Phone (worked on my Android). Also you can pre-download high res tiles onto your phone - but suggest you set the app to store them on micro-SD, not phone memory (if you have a micro-SD).
We used these maps biking in N Spain recently to find trails (along with Google/WikiLoc/Strava), the official 1:25,000 Spanish topo maps were basically useless for biking.
Post edited at 16:37