Not really for mobiles.
With the help of Mobile Fun I found this one. When it arrived I found that Z & Y were transposed (just stuck on my own labels) and that the shift key didn't operate the keyboard as it should.
On enquiries at Samsung I discovered that this is not really compatible with phones and is mainly for tablets. Pity. The keyboard is a decent size and you can type on it properly. It is useable but if you want to use any of the shift keys you need to use the phone keys instead.
So just about OK for the purpose. It is rather large, it doesn't fold, but it is light and thin enough to fit in a briefcase.