My iPad only shows Other, no music or Apps

Ugh. I've seen this on both my iphone and ipad since iOS 7.x came out. Restart both the ipad and the computer, plug it in and see if that makes a difference. If not, try a sync, if that doesn't help try a restore. Try changing settings in the summary screen. Simply switching on Sync Over WiFi fixed it on one occasion

I don't know if it's a bug in iOS or iTunes, but it's a pain.

still a recurring issue:
even after hard reboot, force quitting iTunes, disconnect and reconnecting my device, restarting my computer; the issue still persists:

Everything is 'other'. Stuck in a perpetual loop of rebooting, reconnecting and I still can't sync as it's greyed out.

Hi, I know this is an old thread, but did you try initiating a sync from the iPad (Settings -> General -> WiFi Sync) while it is connected to the Mac? That solved the issue for me.

It's a persistent problem. I've even had it happen under iOS 9.x. Apple doesn't seem to be too concerned since it's an intermittent problem and a restore or two from a backup usually fixes it.