I assume the “Waiting” you are seeing is on the home screen along with all of the other apps?
It could be that there are a number of apps being installed, and Anytune is in the list to be updated, but it just hasn’t happened yet. It could also be that some other have gotten stuck and are making it take a long time.
You could try rebooting your iPad to reset the downloads. You could also try using iTunes to download all of the app updates, and then use it to sync the apps over to your iPad.
Hope something in there helps. I’m sure you’re not the only one to run into something like that after updating to iOS7. 🙁