gkschmall provided the answer I needed. I'd like to add a bit.
gkschmahlJul 4, 2015 8:57 PM in response to Joedon1946
Level 1 (5 points)
Jul 4, 2015 8:57 PM Re: "Null" app can't be deletedin response to Joedon1946
I had this same problem and just today was able to get my "null" app deleted!! This problem was also causing my backups to fail (either to iTunes or to iCloud). I am on a 6 running iOS 8.3.
Go into Settings, General, Usage, Manage Storage. Once there, find the "null" app and at the far right, touch the Right Arrow ">" to take you to the specific App detail screen. There I was able to see some of the details of the app to let me know which one it was (see picture below). In my case, the Blue Infinity logo helped me find it in the iTunes store...under Purchased Apps. Delete the App from this detail screen right now. Then go find it in your list of Purchased Apps and re-install it. Once re-installed I was able to do a backup to my computer...then I was able to delete it completely! Good Luck! Hope this works for you too.
I plugged my phone into my computer, launched iexplorer (I have a paid version; you may be able to do this with a free version), clicked on apps, and any app that looked like a web page ended up being a null app on my phone. If an app said CNN with an icon, it was not a null app. If there was just a blue icon with an A and then something like com.google.gmail, it was a null app. In the next column was usually the app name or a clue to what it was.
Then on my iphone I went into settings>general>usage>manage storage (NOT icloud). I tapped on one null app, found version number and size (size was always slightly smaller in itunes), looked at the suspect apps in itunes to get a match. When I knew which one it was, I used the manage storage on iphone to delete the app, only the one, then went straight to the app store, looked in my purchases, searched for it, and downloaded it. The app downloading would show the actual icon, not the bullseye, and would always stall at around 8o'clock. At that point I held it to make the apps jiggle, pressed the x to delete it, waited for it to disappear, and then it was really gone.
I had to do this step one at a time for 8 null apps I had. Then I could finally make both itunes and icloud backups without errors.
POSSIBLE CAUSE: In my case, I was deleting apps from my iphone, which on itunes sync tried reinstalling them, but I was in a hurry and so I stopped the sync and these ended up in limbo null land. Special thanks to gkschmal who figured it out for me!