Part of yesterday’s iOS 4.3 update was a feature that now requires a password to be entered a second time for all in-app purchases.

The move has been made in response to parents who want to control what little Johnny buys through his iPhone apps and games.

A password has always been required to make a purchase, but it would usually hold in the system for around 15 minutes, meaning that small children could easily hit 'buy now' without having to re-enter it.

An Apple spokesperson told the Washington Post, "We are proud to have industry-leading parental controls with iOS.

"With iOS 4.3, in addition to a password being required to purchase an app on the App Store, a re-entry of your password is now required when making an in-app purchase.”

Obviously the trick here is to not let little Johnny know the password in the first place.

You can read more about the iOS 4.3 update here.