In the beginning of April Apple unveiled the features of new iPhone OS4 which was renamed as iOS 4 at the event of WWDC 2010 when the new iPhone OS 4 was announced.
Apple also rolled out the Global Master Candidate of this new iOS 4 for developers at the event. The public version of iOS 4 is being expected on June 21. However, if you want to update your iPhone and/or iPod to this new version, we have managed to get the download links of iTunes 9.2 beta and iOS 4 GM Release.
Before proceeding to the update process, have a look at these screenshots of iOS 4 posted by Taimur on his blog.
Lock Screen in iOS 4
Change Wallpapers in iOS 4
Change Wallpapers in iOS 4 (2)
Game Center in iOS 4
Game Center in iOS 4 (2)
Folders in iOS 4
Folders in iOS 4 (2)
Editing Apps in iOS 4
Multitasking in iOS 4
Mailboxes in iOS 4
Mail App
Digital Zoom in iOS 4
Bing in iOS 4