Weird syncing issue with iTunes
When syncing my iPhone 6+ to iTunes 12.3.0.44, and selecting Apps under settings, instead of seeing my Apps organized in the window to the right, there's just a rotating circle. I am able to organize the Apps on my iPad 3 and wife's iPhone 5. I've just updated to iOS 9 on all three devices, tried a hard reset on the 6+, restarted iTunes, as well as the computer which is running Yosemite, to no avail. Also tried repairing Disc Permissions.
iMac (27-inch, Late 2012), OS X Yosemite (10.10.5)