My four year old became interested in learning how to write letters at the beginning of the school year, with the expectation at preschool to write his name to sign in each day. He is very resistant to instruction from us on how to form letters, but he loves working with this app. I love how customizable it is, with user-defined word lists, different fonts (currently Zaner-Bloser, DNealian, and Handwriting Without Tears), and the ability to finely tweak different aspects of difficulty. I also like how I can see what my son has been doing with it.
I contacted the author to ask whether he would consider adding Getty-Dubay Italic style to the program, and he is considering it for the next revision! He is incredibly responsive and nice. What a great set of apps hes made - I think we have all of the English-language ones now except for the cursive one.