Has a lot of good material but very unbalanced - lots on birds and geology, much less on history. User interface is dreadful e.g. can't see a map of the whole island showing the walks, must download each one individually before you can find where it is! Map keeps jumping to current location so it's hard to plan a walk in advance. Maps are very good on terrain but miss out significant buildings and features. Could become very good but now expensive for what looks like a beta.
Kefalonia topoguide at Google Play market analyse