I am considering getting an iPhone 4 when they are available in Thailand (or an import from Singapore) but im a little worried about the multi-tasking aspect of the phone.

I currently own and use a HTC Desire (Andriod phone) and i love it, its a great phone and handles everything well... i've read that the iPhone 4 doesnt do multi-tasking properly, it will suspend and save the state of an application when you try to switch between them, meaning if your using something like MSN Messenger or Google chat, you will get signed out and not be able to recieve messages. Is this true?

I want to be able to do things like listen to music, have my MSN client running in the back ground and then check emails/surf the web at the same time, i can do this on the Andriod phone easily enough, but is this possible on the iPhone?

What are the limitations of the iPhone's multi-tasking?

I have the 3Gs which has the multi-tasking. I can listen to BBC radio 5 then switch to Safari and the radio still plays and I can kick off MSN Messenger and switch to any other application and get a pop-up notification when someone MSN's me. I'm not sure that the multi-tasking works for all software but it does for the software I'm interested in using.

True Multitasking at the moment is possible only for brand new applications which support it. All older software not yet updated for iOS4 can't multitask, they will suspend instead and practically closed, but still present in the background and eating memory and resources.