Tech giant Apple has confirmed it will start rolling out an update to its iPhone operating System, including its App Tracking Transparency (ATT) feature next week.
As it will allow users to effectively opt out of receiving adverts, ATT is seen as a threat to the online advertising industry, especially companies relying on targeted ads.
Facebook last year took out newspaper advertisements saying the move will impact small businesses by making it more difficult to run personalised ads and reach their customers.
After iPhone users install iOS 14.5, when they open any app which wants to access the Identifier for Advertisers, they will see a pop-up. That asks them if they want to be tracked and gives them an opportunity to opt in.
Apple has said all apps submitted from 26 April must be able to support ATT and earlier this month urged developers to ensure their apps were ready for the new software. The company says it is prepared to remove apps which do not comply with the new policy.
A new purple iPhone going on sale from 30 April will have ATT pre-installed.
Apple usually releases major software updates on Tuesdays.
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