In case you have been wondering how to operate your brand new iPhone 4, then Apple has released a user guide for iOS 4 software. It’s a 17MB, 244 page PDF designed to walk you through everything from syncing to using the default apps.
The guide is 28 chapters long and covers everything from Mail, Safari, iPod, Messages (SMS/MMS) to recording video. While the manual is really mostly filled with tips and advice which are specific to the iPhone 4, there are also tips for the 3GS and 3G. When a section of the manual is only applicable to a certain device, it is noted at the beginning of the section.
If you are looking for other Apple related manuals then you can check Apple.com where there is a whole section of Apple manuals for various devices including the iPod and iPad.