I believe they are quite a few External Keyboards that are available in the Market which You can be attached with the iPhone 4 and iPhone 4s I wonder if anyone here who has used any of those here can recommend which is the best keyboard for iPhone 4s.
Seems you like physical keyboard other than touch keyboard just like me, I would like to recommend Bluetooth Sliding keyboard , very easy and convenient to use, perfectly compatible the iphone 4/4s.