For information on everything you ever wanted to know about iOS 6, you can download the free Apple iphone user manual directly onto your idevice from iTunes. You will first need to have the free iBooks app downloaded onto your idevice and be connected to internet/WiFi. Once this has been done, then:
The user manual will show up on your bookshelf. Handy to have with your phone all the time – I like being able to refer to the Accessibility information. iOS 6 has added new accessibility features but if you or your client rely on using Google Maps, you may want to hold off on updating to iOS 6. The new iOS 6 has its own Maps version (Google Maps will disappear from your idevice) but it does not have street view, and does not show transit options/times. More importantly, the iOS 6 Maps is not as accurate as Google Maps.
I have downloaded the mobile version of Google Maps, but I prefer the way Google Maps used to work with iOS 5. Time will tell if Apple can get their map version up to Google standards.