Thread: I need some help from the computer/iPhone/iPad literate please.

Moderators please feel free to remove this if it is not appropriate.
While I can use my pc, iPhone and iPad fairly well I am not able to solve the current problem I am in the midst of. I am 65 years of age and marginally computer literate so that may explain some of my ineptness.
Yesterday I brought up iTunes on my PC in order to update the software and sync my iphone and ipad and PC.
When I could not remember my tunes password I was finally prompted to change my login and password for itunes. This i did before I plugged in my iphone and ipad for a synch and sofware updates. I can log into itunes with
the new user name and password with no issue via my pc. Every thing music wise and other is all there. The problem comes when I try to update my app's on the iphone and the ipad when not hooked to the pc directly and the password entry screen comes up showing my old login info. The new password does not work of course, and I cannot find the means on either the phone or the pad to make the correction for the new login. When I go to itunes store in settings on my phone and pad my new apple ID shows up. But I have had no success trying to update the app's. Thanks for any help it is much appreciated.