But Apple gives and takes away, in this case iOS 6 removes the default Google Maps app from the device. This removes Street View along with Google
What's the most useful feature?
Probably the biggest, most useful feature is the expansion of iCloud, which now includes Documents In The Cloud. This integrates with apps like Pages, Numbers, and Keynote. iOS 6 will also expand current iCloud functionality for data from calendar, contacts, and downloaded products. iOS also integrates closley with Mac OS X 10.8 Mountain Lion.
What are the other big features?
Facebook integration is a big deal in iOS 6 and you can sign in in the iOS Settings and post from various places like Safari and Notification Center. It also syncs your contacts with your Facebook account so if people change their details on Facebook it'll update automatically on your iOS devices.
It won't be new to iPhone 4S owners, but Siri now makes its way over to the new iPad and now returns information on sports and businesses.
Anything new that's phone related?
Indeed, there are two new Phone features. One is called Remind Me Later that is a quick way to skip a call but be reminded to call back. You can be reminded in an amount of time, or when you leave your current location (or when you arrive somewhere, like Home or the Office).
You can also use Facetime now over 3G, which will open the floodgates for Apple's video service. You should keep an eye on data usage though if you plan to use Facetime on 3G on a regular basis.
Anything new for Mail?
The mail app has the new VIP inbox feature from Mac OS X Mountain Lion that only displays emails from people you've highlighted (by favouriting in Mail or Contacts). It's a great way to view emails from just the people you're interested in.
What's this Passbook I've heard of?
Passbook is a completely new app from Apple that displays vouchers and receipts from companies that have designed apps to work with Passbook. A typically example is that you book an air ticket with a supporting company (say British Airways) and your ticket is sent directly to Passbook on your iPhone. Because it's location-aware it'll serve up tickets when you arrive at the airport, and the barcode displayed on the screen of the iPhone is your ticket to board the plane. It sounds great, but will depend on support from companies. It's all part of Apple's long term plan to integrate the iPhone with businesses and the retail environment.
Anything I probably haven't heard of?
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