Apple’s next privacy update has developers looking for dodges

App developers are exploring new underground forms of user tracking to evade Apple’s new privacy rules, which threaten to shake up the mobile advertising industry in the months to come.

In early 2021, an iPhone update will prevent apps from using advertising identifiers called IDFAs without obtaining each user’s explicit consent for targeting. Developers expect more than two-thirds of users to block tracking when they see a pop-up window appear in their apps.

Some app makers say they plan to use invasive tracking techniques such as ‘device fingerprinting’ to bypass the new restrictions, even though doing so risks getting them rejected from the app. Store if they are captured.

“At 100%, everyone will try to fingerprint whether or not Apple enforces its rules,” said one mobile game developer.

Privacy activists have welcomed Apple’s changes, but warn that it is never possible to eliminate tracking entirely.

“There will always be follow-up,” said Andrés Arrieta, director of consumer privacy engineering at Electronic Frontier Foundation, a digital rights activist. “We’ll always see apps trying to do bad things. No matter what you do, you will have these bad actors.

Facebook criticized Apple’s change, removing a series of newspaper ads in December that accused Apple of depriving app makers of nearly half of their ad revenue by removing personalization.

Few other developers are ready to fight publicly with Apple, whose App Store acts as the guardian of a $ 500 billion economy. But privately, the creators of some of the App Store’s most popular apps are concerned, given the importance of advertising as a vehicle for both revenue and distribution.

“The impact is almost impossible to predict,” said the head of a major mobile game developer.

“It’s a huge, huge change,” said the head of another major mobile game developer. “This is the greatest risk we have [as a company]… It could really affect us negatively.

Developers fear that many players in the advertising industry are still unaware of the scale of the changes to come. “Brands and agencies have no idea – they don’t know exactly where the ecosystem is going,” said a politician at one app maker. “Technology intermediaries are forced to solve the problem.”

Under such pressure, some developers are desperate to use new, more invasive forms of tracking, even if users deny their apps permission to use IDFA.

The device’s fingerprinting can be used to recognize repeat visits from the same smartphone, even across multiple apps. The technique, which is prohibited by Apple App Store rules but can be difficult to detect, works by correlating a combination of a device’s hardware and software characteristics, configurations such as internet connections, battery or language and usage patterns.

Another way to track people between apps is to use the same email address to sign up for various services and games. “Hashed emails,” where addresses are transformed into a string of letters and numbers, allow businesses to share user details without passing an individual’s email address directly to their partners.

While these techniques may be difficult for Apple to detect, the cost of getting caught – and losing access to the world’s most lucrative mobile storefront – could be huge. “Do you want to play with fire?” asked a developer.

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