I used iPhone 4s in 2014. not much satisfied with the features with that price range. There is no such difference iPhone 4S Vs iPhone 4. Battery life is very important feature of any mobile phone but battery life is low as compare the other equivalent phones. Not a very large to my Video and pictures to other.And above all not compatible with 4G Network.
Also many local language Apps not properly works on the same phone. I also post question on iPhone developer forum but no regional Apps work.
Conclusion: The iphone 4s not fill my expectation, on that price range you would find more high feature phone on Android platform.
Thanks