Can I pre-download iOS update for iPad? I purchased  an iPad for my parents who live 2 hours drive away from me.  The only internet connection they have is the 3G sim chip in their iPad.  I want to apply the iOS 5 update, but in order to download it the iPad seems to be required to be plugged in to my iTunes, which is really inconvenient.  I also would ned to provide my laptop with a wifi connection from a hotspot on my iPhone, which does not seem stable enough long enough to download the iOS update.

It would be so much easier if I could download the update while at home over my fast fiber optic network connection, then drive the two hours and apply the update.

Is this even possible?
When iOS is updated, an .ipsw file that is downloaded from Apple's servers by iTunes. You can find direct links to them at iDownloadBlog.

At your parents' house, to update iOS, plug their iPad into a computer and launch iTunes. Then click it in the left sidebar and hold down the &uArr; Shift key while clicking on the Restore button. This brings up an open file dialog; simply look for the .ipsw file you downloaded and open it. 

iTunes will tell you that the iPad will be wiped and restored, just click OK and give it time to update. You'll be asked whether you want to start again or restore from a backup when the process finishes; choose the newest backup and the previous data on the device will be loaded back on.