In reply to Philip:
I used UKH when I did the Wainwright's, but it helped that there was already a tick list set up for them. Other apps are a pain as you have to tick each hill one at a time, which is cumbersome (did 22 Birketts one day) However, UKH doesn't give you the nice visual map of your summits, so I'm using Walk Lakes, which is the best of the rest, but only covers the Lake District I think.
If you don't need the map, UKH is easiest, and obviously familiar if you use a log book on UKC. Also allows you to add hills really easily