Apple app developers will soon be able to email customers and tell them how to avoid Apple's payment systems.
The current rules ban app makers from mentioning that there are ways to pay that avoid Apple's 30% cut, even through e-mail outside the store.
But as part of a $100m (£73m) legal settlement with developers, the tech giant is changing its policy.
Apple said the change was a "clarification" and part of its "efforts to evolve the App Store".
The terms are still subject to judicial approval. Once active, developers will be able to use email addresses gathered from their App Store customers to email them about ways to pay outside of Apple's system.
Apple said users must consent to such emails and have the right to opt out.
$100m fund
The row between Apple and some of its developers over its 30% cut has been rumbling on for years.
Apple has already made concessions - for example, dropping the cut to 15% for businesses who earn under $1m, or for recurring subscriptions after the first year.
It is a core part of the Apple-Epic legal battle, which started when the Fortnite maker put its own payment option into its game - at a lower price - and was swiftly banned from the Apple and Google app stores.
But this new change is limited in scope, and does not allow alternative payment options inside apps the way Epic implemented it before its ban.
Developers still cannot add their own payment system directly into apps or use in-app notifications to tell people about other ways to pay.
And Apple's other rules - including what kinds of apps can use external systems - remain largely the same.
The settlement of the class action lawsuit brought against Apple also involves a payout for eligible developers of anywhere from $250 to $30,000 each from the $100m fund, depending on how many apply and their history of working in the App Store.
Apple has also pledged to introduce more price points for developers to choose from, giving app makers many more options than they had before, and to publish an annual transparency report with details about App Store approvals, app removals, and more.
'A big deal'
The settlement also includes a commitment to maintain some existing developer-friendly policies for at least a few years.
Richard Czeslawski, one of the app developers named in the case, said the ability to use customer information to tell them about their options was "a big deal".
In a filing with the court, he said it was a "game changer" because the ability to communicate effectively with his customers was the lifeblood of his business.
Developers will "take full advantage of this change… as a way to further reduce the commissions paid to Apple", he said.
The Coalition for App Fairness - a cohort of developers set up to campaign against some of Apple's policies, including household names such as Epic Games and Spotify - said it was a "sham settlement offer".
It labelled the deal as "nothing more than a desperate attempt to avoid the judgement of courts, regulators, and legislators worldwide" and argued it does nothing to address underlying issues.
"App makers will still be barred from communicating about lower prices or offering competing payment options within their apps. We will not be appeased by empty gestures," it said.
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Apple said it "appreciates the developer feedback and ideas that helped inform the agreement".
"The updates constitute the latest chapter of Apple's longstanding efforts to evolve the App Store into an even better market place for users and developers alike," it said.
Separately, Apple also announced its "news partner programme" - a change to its agreements with news publishers who contribute to its Apple News product.
Those publishers will only be charged a 15% commission fee on "qualifying subscriptions" for their news app from day one, avoiding the full 30% fee entirely.