Apple has added extra paid-for advertisements to its App Store, a week after its new operating system limited tracking for ads from other companies.
The new ad space lets app-makers advertise on the App Store search tab, rather than just in the search results.
Last week's release of iOS 14.5 placed strict limits on tracking on iPhones - including tracking for advertising.
And Facebook fiercely opposed the change, warning it would favour Apple's own advertising system.
Apple's App Tracking Transparency feature requires apps on iPhones to ask for permission to track the user for advertising.
During a long-running row between the two, Facebook had warned Apple's "privacy" features would hurt advertisers - including app makers - and benefit Apple.
"Apple's policies leave very limited options for app developers to find customers through effective advertising - and, conveniently, Apple's own advertising products is one of them," Facebook had said.
'Increased demand'
Previously, Apple sold adverts to appear at the top of search results only. The new slot effectively doubles the advertising space for sale.
Enders Analysis senior media analyst Jamie MacEwan said: "The timing makes sense.
"Apple probably anticipates increased demand for exposure on the App Store. That's because Apple's iOS privacy changes have made other options less attractive."
Ad campaigns on other sites had less reliable measurements of success, he said.
And app developers ran ads only if they were sure the cost of winning new customers was lower than the amount they would spend on the app.
"As its ads business grows, Apple will have to make sure its execution on consent and privacy is impeccable" to avoid accusations of putting itself first, Mr MacEwan added.
Some reports suggest Apple's ad sales could be worth more than $2bn and are growing.
Apple has not responded to a request for comment on the timing of the new advertising product launch.
Legal battle
The new feature also comes as internal Apple emails reveal a tension in the company over its advertising business.
The emails, between Apple employees in 2015, discussed the possibility of adding adverts to the App Store, after Google launched them for its own Android store.