How to re-update Android version 4.4 KitKat? 3 days ago, my Nexus 4 smartphone started to update its Android version from 4.3 to 4.4. During the update process, there was an internet problem. Because of that, I guess the new version 4.4 Kitkat was not completely installed. Some functions are missing; some of them are installed. 

Can anybody tell me what to do?
What you describe can't happen. The Android updater downloads the whole update before doing anything. Only after it's finished downloading does it offer to restart and install, and no internet connection is required for the installation procedure.

Perhaps what's happened is simply that the Android update has completed successfully, and you're waiting for some apps to update themselves. New functionality like the Play Newsstand app is separate from the OS update, so you might have to wait a little longer for that update. Also, if you're expecting the new home screen, with a Google Now page and transparent effects, be aware that that also isn't part of the OS update: the new launcher is only on Nexus 5 devices for now, and you'll be able to download it from Google Play soon.

When you're trying to get help with a problem, describe the actual symptoms you're seeing, not just what you think caused the problem. We could give you much more specific answers if your question were more specific than "some functions are missing".