I hooked my iPhone 4S up to iTunes last night and, lo and behold, a box popped up to inform me iOS 6 was available. Ten minutes and a reboot or two of my phone later and I had…pretty much the same phone.

This had me wondering, exactly what features were installed with this upgrade?

• Decline calls—“iOS 6 adds new calling options that give you more flexibility over how you handle incoming calls that you don’t want to take,” Jeffrey L. Wilson wrote in PC Mag. “Instead of simply declining a call, you can now reply to it with a text message (either pre-fabricated or custom) or set a reminder to follow up with a particular person later. You can see the new options by swiping the screen upward when a call comes in.”
• Passbook—This is the first change you’ll notice after the upgrade, since it’s the only new icon that pops up on your screen. As I wrote previously, Passbook will hold your loyalty cards, airline and movie tickets, and, some are speculating, eventually your currency. It was good to know we don’t all have to buy the iPhone 5 to have access to Passbook.
• Maps—If you have iPhone 4S, you’ll have more features than if you have an older phone. Voice command works through Siri, so obviously you’ll have to have a 4S or 5 to access that feature. You’ll also only have access to iOS 6 Maps’ “flyover” feature if you have 4S or 5.
• Do Not Disturb—Once you’ve upgraded to iOS 6, you have to go into Settings and turn Do Not Disturb on. There you can set up your phone to leave you alone during certain hours. During these hours, your phone will remain silent and dark, which is great for those of us who are tired of our iPhone screens blinking on and off throughout the night. Just under Do Not Disturb, you’ll notice an option called Notifications. Click on this and choose Do Not Disturb. Here you can choose to allow calls from your favorites, all of your contacts, or none of your contacts. One word of warning, though. If your iPhone is your only source of contact with the world, it might not be wise to drop all phone calls at night, since an emergency call can come through from someone who isn’t even on your contact list. (Say, for instance, a police officer calling to tell you a loved one has been in a car accident.) You can set up Do Not Disturb to not silence a call if it comes in twice within a three-minute period, but I’m not sure I want to take that chance. Instead, you might want to accept phone calls from everyone, which will silence all text messages and other notifications.
• Facebook integration—This will make sharing things with your Facebook family a little easier, which, of course, is the last thing the world needs. But users want to be able to share every facet of their lives with the world, so this integration is a welcome addition to the Apple operating system.
• Bye bye, YouTube—Yes, the iOS 6 upgrade wiped YouTube right off my phone. Of course, you can download the YouTube app, which was the top free iPhone app the last time I checked, but it’s still a little annoying that an app was removed from my phone.
• FaceTime over cellular—This will likely only apply to you if you have unlimited data. These days not many people do—those who do will probably lose it when they upgrade. But FaceTime will now work over your cellular network, allowing you to see your friends and family as you’re roaming the world, talking to them. You’ll still probably want to seek out a wi-fi for your FaceTime chats, but it’s nice to know this feature is now an option.

To upgrade, hook up to iTunes or go into Settings-General-Software Update.