Additional marketplaces aside, one of the specific complaints mentioned in the article is that some iOS system APIs are private, usable only by apps that Apple

Additional marketplaces aside, one of the specific complaints mentioned in the article is that some iOS system APIs are private, usable only by apps that Apple itself produces. "private APIs and system-level integrations that Apple claims provide for better battery life, messaging management, etc.; the DOJ says that these integrations should be modularized and made available" While messaging management makes it sound like the DOJ potentially wants Apple to give 3rd-party apps read access to users' SMS messages, the battery life API seems innocuous, yet batteries have already seen use in fingerprinting: "Fingerprinting happens when an app takes innocent-looking but technical information from your iPhone, like the volume, battery level and IP address. Combined, those details create a picture of your phone that can be as unique as the skin on your thumb." [1] Apple responded [2] to this type of fingerprinting by requiring app developers to give good reasons for requesting it, but a 3rd-party App Store would offer limited if any oversight from Apple. "'To prevent the misuse of these APIs […] developers will need to declare the reasons for using these APIs in their app’s privacy manifest,' Apple says. 'This will help ensure that apps only use these APIs for their intended purpose.' ... The data includes points such as IP address, screen resolution, language setting, fonts used, operating system type and version, processor type and speed, network information, battery level, etc." [1] https://www.washingtonpost.com/technology/2021/09/23/iphone-tracking/ https://www.washingtonpost.com/technology/2021/09/23/iphone-... [2] https://www.bitdefender.com/blog/hotforsecurity/want-to-fingerprint-an-iphone-user-tell-us-why-says-apple/ https://www.bitdefender.com/blog/hotforsecurity/want-to-fing...