I am working on a 'fun' Facebook app that asks ten questions and presents you with a 'fun' result. We need to ask permission to access some of the users data, this consists of their 'Basic Information' and posts to their Wall. In your opinion, is it best to ask for these permissions up-front or wait until they have finished the quiz, just before the resolution? So it would be 'If you want to see the finished result, grant you permission' basically.
The thing is, if they decline the permissions they do not get the resolution at the end, the app would bomb out and drop them back at the beginning.