If you do use the app and it crashes, please send a crash report and a short description what you were doing. It helps me a lot figuring out what the problem is. I post up known issues at https://trello.com/board/shortcat-bugs/51ac6a3711f6b34606001... (public Trello board) so people can vote and comment on issues.
I strongly suggest reading the README as I haven't baked in a tutorial to the app just yet.