facebook: changing permissions of an existing application

We have already launched an application, but we clearly see now, that we need publish to wall permission (our approach with not requiring this from user and basing on invites doesn't work well). Can we do it? How to make sure, that users will be instantly notified about the need of accepting new permissions, rather than having our application malfunction, if they don't have开发者_JAVA技巧 them yet?

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Basically, it will allow current user to perform only the permission they granted. But there is a trick to solve the malfunctioning of app as permission is changed.

Always put the permission button as first step for the application. So that if user has already given all the permission to app, it will automatically redirected to next_step mentioned. If there is all/any permission added, it will ask only for updated permission to users.

It will make your app work with new as well as old users.