To share to Facebook from within your iPad app, Facebook requires that you create and register an app through their developer portal.

The portal is located here:

You will need supply Realview the following:

You can also choose what the app will share on Facebook:

Facebook App
If you have a Realview Facebook App, sharing from within the app can post links to that. This gives you the maximum social proliferation.

Online Edition
Posts to Facebook link to the online version of  your publication. Ideal if you don't have a Realview Facebook App.

iPad APP
Posts a generic link to the app within the Apple App store.