Apple in iOS 13 introduced a change that limits data collection practices using VoIP APIs, which has consequences for messaging apps like Facebook Messenger and WhatsApp.
According to a new report from The Information, the makers of encrypted messaging apps like Signal, Wickr, Threema, and Wire are now scrambling to overhaul their software to protect key privacy features that they believe may be compromised by the changes.
In a statement to The Information, an Apple spokesperson said that Apple is working with developers to alleviate their concerns.
"We've heard feedback on the API changes introduced in iOS 13 to further protect user privacy and are working closely with iOS developers to help them implement their feature requests."
Julia Weiss, a spokesperson for Threema, said that Apple's changes may actually result "in the opposite of the privacy goals the changes were supposed to achieve."
What Apple is doing is limiting the PushKit API, which was designed to be used for VoIP calls but over time, has also been used for other purposes such as collecting data and, in the case of messaging apps, encryption. In iOS 13, the PushKit API is limited to internet calls, with Apple eliminating its other uses.
Encrypted messaging apps currently use the VoIP APIs Apple is restricting for decrypting messages on the iPhone in the background, and the change disables that functionality.
App developers will be able to work around Apple's changes, but Tom Leavy, a VP at encrypted Messaging app Wickr said that it's a "significant engineering effort" that was unexpected. Makers of encrypted messaging apps are said to be exploring "alternative tools" in iOS to work, but they're said to be "way inferior" to the existing PushKit option.
Apple is giving app developers until April 2020 to comply with the changes to the PushKit API, but developers who want to update their apps for iOS 13 and take advantage of new features must follow PushKit restrictions sooner.