Ok, I have a Rails app using the Koala gem. I have manage_pages permissions and I'm able to successfully get the user's pages and access_tokens.
I want to add an application with a Page Tab to one of the user's pages. Basically the equivalent of going to an app's profile, clicking "add to page" and selecting a page to add it to.
I don't see where in the Graph API this is done.
If you have the manage pages permission using the Graph API you can install a profile_tab at the end of the current list of installed tabs for a page by issuing an HTTP POST request to PAGE_ID/tabs with a Page Access Token
https://graph.facebook.com/YOUR_PAGE_ID/tabs/create/?app_id=YOUR_APP_ID&access_token=YOUR_TOKEN
Hope that helps.