I’m looking through some logs trying to explain some “interesting” behavior and I’m seeing some users come to my application with a user agent similar to this one:
Mozilla/5.0 (iPad; U; CPU iPhone OS 5_1_1 like Mac OS X; en_US) AppleWebKit (KHTML, like Gecko) Mobile [FBAN/FBForIPhone;FBAV/4.1.1;FBBV/4110.0;FBDV/iPad2,1;FBMD/iPad;FBSN/iPhone OS;FBSV/5.1.1;FBSS/1; FBCR/;FBID/tablet;FBLC/en_US;FBSF/1.0]
If I run this string through udger.com I get the following result:

This screen shot and user agent confuses me because it says it’s the mobile safari for iPod and iPad. I see iPad in the first part of the user-agent, but I also see a lot of references to FB and iPhone and iOS and all kinds of other things.
I’m curious if this is a “generic” user-agent that is served up by the Facebook for iOS application, and if it is – is the device an iPad or is it just not clear enough to tell?
Yes it is the iOS Facebook app….
The following is the user agent string from an iPhone 4s showing that it includes the correct device
iPhone4,1The devices shown seem to follow the same model identification shown in an answer on detecting iOS models
This means the string you show that it was an the facebook app on iPad 2