Note: Some users yesterday reported problems getting the iOS 5 update to install on their iDevices. Speculation centered around overloaded Apple servers as the culprit. So you might want to wait a day or so before trying to upgrade.
After iOS 5 is installed, your device -- I'm generally focusing on the iPhone for this review -- will restart. The first thing you'll notice is the new Setup Assistant, which is very similar in theme to the one in OS X Lion. Once you pick a language and enable/disable location services, you have to choose to connect to a Wi-Fi network or use iTunes to activate the device. (Despite all the talk of cutting the cord, you still need a Wi-Fi connection or access to a computer with iTunes to go further. That shouldn't be a big deal if you're upgrading your phone from home, but if you're snagging a new iPhone 4S, be sure the activation is done before you leave the Apple Store.)
Once a network connection is established, a tap of the Next button begins the phone activation. In a minute or so, you can set up your phone as new or restore from your iTunes backup. This is where you'll be happy to have backed up before you upgraded; once the iTunes restore is complete, your device should be exactly as before, except now it's running iOS 5.
With the arrival this week of iCloud, you'll also be able to restore your device over the air in the future. Basically, your phone gets backed up to iCloud when it's not in use, and restoring it using the new service will be like using iTunes -- except you don't have to connect your phone to a computer. With iCloud, user data like notes, app/OS settings, text messages, mail accounts, contacts and calendars are downloaded first. After a reboot, camera roll pictures and applications begin downloading, with apps even remembering their location on the home screen.
Here Apple added a nice touch: If there's a specific app you need to access right away, a simple tap of its icon pushes it to the front of the download queue during the iCloud restore process. With iCloud restores, you still have to wait for everything to download to your phone, but at least you can start using the most important app right away while less-important apps and files are retrieved in the background.
During the iCloud restore (or after an iTunes restore), if you previously used a passcode to access the iPhone, iOS prompts you to create a new one.
Although Apple talks up 200 changes in iOS 5, there are a handful that stand out.
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