My iPhone 5 won't update apps?

I had the same problem on my old iTouch 4th gen. When I go to update an app, it asks for my password so I put it in and it says installing and then stops updating and says update again. Any one else have this problem? What do I do?

Added (1). I did. Doesn't do ***. Lol

Connect your phone to iTunes.

My does the same thing! UGH! Very frustrating. I deleted the app and had to reload.

my iphone wont update my apps

But where do we put the code in at?