Can I do Icloud on my iPhone 4?
Yes, as long as you upgrade the phone to iOS 5.
Yes u can with IOS 5!:)
You can even use the cloud with your 3GS too!
What is the icloud
It's possible!! You will have to update your phone to the 5.0 version first.
Yeah, there was an early preview back in the summer and iOS 5 is now out so you can do everything with iCloud and not just the downloading previously purchased content.