I was just playing with the iOS sample code of the facebook sdk, however I am seeing a screen like this when I login:

Now usually in other apps, I don’t see the web address and the search bar. I only see facebook in the tab bar. So how can I achieve the same thing?
When you ask the Facebook API to authenticate the user, it will try to launch the Facebook app if it’s installed; if not, it launches Safari instead. Since you don’t have the FB app installed on the simulator, it’s launching Safari on the simulator.
If you test on a device instead that has the FB app, then you’ll see it launch that as expected.