An Outlook user writes:
I need to be able to view other people's Exchange calendars on my iPad. On my iPad I can see one of my Colleagues calendars but all of my colleagues have shared their calendars out to me and given me full owners permissions, but I can't see their calendars.
The reason you can see the one calendar in your mailbox is because you copied the calendar to your mailbox. This is a copy of the calendar as of the day you copied it and it does not sync with the original calendar.
You cannot see other user's calendar's on an iPad (or iPhone, Windows Phone, Android, or BlackBerry) as these devices only sync your own calendars. You will need to copy the calendar to a folder in your mailbox in order to see it on the device.
Additional Sync tools can be found at
Synchronizing Exchange Mailboxes and Public Folders