You can authorize up to five PC's with iTunes, but that should not be confused with syncing your iPad. The iPad should be synced with only one computer. Doing otherwise will quickly lead to problems. Depending on the computer's settings in iTunes, syncing your iPad will copy any newly purchased apps to iTunes. Those apps will not show up on the other computer unless you set it up to automatically download new purchases from iTunes. You can do this in the computer's iTunes Preferences, the Stores tab. There is a section called Automatic Downloads were you can choose to automate the downloading of new Books, Music, and Apps. When turned on iTunes will go t the iTunes store and download any new purchases you've made since that last time it was started. You can do the same thing on your iOS devices under Settings > iTunes & App Stores. This will only work with newly purchased apps. If you want to copy older apps to the second computer use the Purchased link at the top of the right column on the main iTunes Store page. I don't see a big advantage to doing this, but it wouldn't be the first time I've overlooked a valid use case. You can also upgrade all the apps on a computer by visiting the Apps section while in library mode. Choose the Updates section from the top and then either update apps individually or all at once.
Hi T Poet.
Big thanks for your reply.
I am aware of the 5 PC authorisations, for Apple one could say that is generous.
You say that one should not sync with more than one PC as it is good practice.
And you are probably right, but I have never seen anything written about only syncing with one PC, so I'm guessing that Apple give tacit approval at least.
For me I live between two places with a different PC in each so I would like to use both PCs as I would use one.
Alas if not possible, then so be it.
May I clarify one point?
ALL apps appear in both PC's iTunes.
The quirk is that in one of them, not all apps appear in the "Apps List" in the left pane.
All the apps appear in the "screen shots" in the right pane. I was just wondering why. Just a quirk of fate I think.
As you know better than me, syncing in iTunes is fraught with traps for us unwary.
Now I just open "Apps" in the iPad, touch "purchased" touch "Not on this iPad" and re install any that are missing.
So easy.
Thanks and best wishes.