What are the best Facebook apps?

other than the official Facebook app for iPhone, are there any other good iPhone apps for posting and replying to comments on your Facebook Page?

I currently use a static fbml landing page, RSS Graffiti - but limit it to 2 posts per day (I don't like to use twitter cloning on our fanpage either). Also I have used the poll app - but this has limited uses, mainly just to engage existing audience...

Before FB's most recent makeover the maximum number of tabs was 10. What are some ways to create 100's of sub pages within a FB business page.

Most "educational" apps on Facebook appear to focus on flashcards and content sharing. Are there any that actually teach a curriculum to - and connect - learners?

Which apps provide the functionality that Myspace used to provide:  Upcoming Gigs, Videos, Photos, Recent tracks, and downloads.

I am looking for Facebook coupon app that would have the option to get printed by the customer with a unique barcode or number and then redeemed in the restaurant!

Unfortunately Facebook haven't developed an official iPad app... so which are the most loved third party solutions?

Assumptions: Youth aren't using email although email powers so much of corporate, asynchronous communication and project-planning. Facebook has already invented their own email product which masquerades as Facebook messaging. It has attachments, read...

Initially, I thought it meant our own app (Momo). However, we didn't have "Like us on Facebook" feature before. Ironically, after we added this feature in our new version, the number of "Third-Party Apps" under Like Sources plummeted...