For the last several days many iPad users have been seeing a blank Updates page in the App Store, while the App Store app icon shows there are updates available.
There are numerous threads about this on the Apple Support Community pages. So far the best, and still quite clumsy, workaround is to go to the Purchased tab in the App Store and scroll through and install your updates from there. This works for me on my iPad, though it’s a pain in the neck to do because even the All tab under Purchased only shows about 50 apps, while I have over 200 installed and well over 1,000 purchased total. So I have to use the alphabetical listing on the left of the Purchased page and go through letter by letter.
This morning I spoke to Apple Support about this issue and was told the following:
— Apple is aware of the issue and says it has been a problem for at least the last 3-4 days.
— It is only affecting the iPad.
— Apple is working on resolving the issue, but there’s no ETA as yet for when it may be fixed and of course no system status type page where users can check on progress or see when the issue is resolved.

I had this problem over the weekend, but rebooting my iPad fixed it.
As of this morning (July 29), this problem seems to be fixed. At least it is now working on my iPad 2.
It appears it is NOT fixed — I have had this same problem on two (2) iPads for over 2 weeks now. I first noticed it on the iPad mini and now it’s the same on my iPad 3. Anyone else have any suggestions for fixing it??
NOT fixed 3:45 PM EDT July 30, 2013
Not Fixed 18:07 CDT July 30, 2013
The “fix” is easy, just force quit the App Store App:
If you have the App Store active, click the home button to get out of it.
Double click the home button, this will bring up your last used apps.
Tap and hold the App Store icon until it wiggles, and click the red “minus” sign.
Go back to the App Store and everything should load normally.
It seems that this may be fixed !! I tried it last evening LATE and it updated the two outstanding apps that did not show up on the ‘purchased’ section.. No notification, but results speak louder than words…
Salute !!