Great Basic Tree ID
It has a hundred trees, as advertised, and it will identify them EASILY by their leaves, i.e. a "leaf key".
Id be happier if it had more trees, as some common ones are missing, and Id like to see an ID key that works in the winter (no leaves), and it could use some more photos of the trees and their features (user submitted, maybe?).
But its the best tree ID app Ive found for under $4 (disclaimer: I refuse to buy one over that price). I havent tried contacting the developer yet, but I will make some suggestions soon.
Davidlow about
TreeBook