just updated my iphone to the ios4 software,what are the main differences?

[mrswoodentop]

SAys it all really,looks almost the same,do I need to change any settings etc?

Yes, turn off in app purchases, they can be hacked into apparently.

You can multi-task now. Press the HOME button twice to move between the different apps.

You can arrange your apps into groups, so making it more tidy.

Um. Don't think there is much more really.

Zoom on the camera

Sorry to sound dim but how do I turn off in app purchases?

If you have multiple mailboxes, you can see all your mail at once.

You home screen wallpaper appears behind the app icons.

Its not that they can be hacked, its that free apps can charge you without you realizing it.

Go to settings, restrictions, it will ask you to set a 4 digit PIN. Then go to allowed content.

Oh thats OK I have that anyway,will have to try the multitasking !

Tee
There was a thread recently about a poster who had a massive visa bill (if iirc it was over £800) from iTunes. She warned about in app purchases.

Trying to sort out the restictions for in app purchases is a nightmare though,so confusing if you have restrictions enabled should in app purchases be set to on or off ?Thought I had it set up right now I am not so sure.