Apple is tackling fraudulent or unofficial iOS and Mac apps by locking screenshots included with app descriptions once they have been approved for sale.

According to Mac Observer, the move is an attempt to stop a scam in which a small number of rogue developers upload screenshots from other popular apps as their own after listing.

Users were then tricked into downloading fraudulent or unofficial apps.

Developers could previously update screenshots for approved apps from within iTunes Connect, without requiring further approval from Apple. They might choose to do this to highlight new features or try a different marketing approach.

Apple said in its developer portal that although screenshots will be locked following approval, developers will have the option to upload new screenshots when they submit code for an update of an existing app or for a new app.

PocketGamer said that developers have criticised the way in which the rule chage was handled, because it will impact the way that legitimate app developers are able to present their products for sale.

For example, placeholders may be used during the approvals process, to be replaced by high-quality graphics from the final app later.

In addition, it was noted that Apple’s approvals team may now become overwhelmed by developers submitting “app updates” in order to change images.