With the announcement of the official Gatekeeper designations under the Digital Markets Act, iPhone owners will soon regain the ability to install apps from outside the confines of a single App Store. This capability has been blocked by the platform for years, requiring that owners of an iPhone obtain their software exclusively through a single platform-locked App Store, whose terms and conditions dictate the types of software that can be distributed, and whose rules demand a percentage of all digital commerce transacted through the apps listed therein.

App Store tariffs and regulations have diminished the range and quality of software available to iPhone owners. They are the reason you cannot browse and purchase books from within the Kindle app, and why the massively popular game Fortnite was disappeared from the entire iOS marketplace in August 2020. Furthermore, a gag rule imposed on app developers forbids them from mentioning other avenues of commerce. The Spotify music app’s [Premium] tab intimates this with a lone pithy statement: “You can’t upgrade to Premium in the app. We know, it’s not ideal.”

But by March of 2024 – the date that gatekeepers must be in full compliance and good standing with the rules of the DMA – joyous gamers will again be able to show off their Fortnite dance mojo from the comfort of their iPhones. Consumers will likely be able to browse and buy books from within the Kindle app, purchase a music subscription from within the Spotify app, and pay for goods and services using their preferred digital payment service provider rather than having one imposed by their device’s operating system. And the door will finally be open for truly free software to compete on a level playing field alongside commercial vendors.

Lest a gatekeeping entity be tempted to simply ignore these new regulations, or take a creatively self-preferencing interpretation of the provisions, the penalties for violations are hair-raisingly severe: between 4% and 20% of the designated gatekeeper’s total annual turnover. With a quarter-trillion dollars of revenue at stake, and under vigilant public scrutiny, we can expect very careful adherence to the letter of the legislation.

What does compliance look like, exactly? For everyday iPhone users, how will you find and install independently-distributed apps? Will they be listed in a separate section of the “App Store” app, or will they have their own separate app management apps? Or will you need to download apps individually using a web browser? If so, how will app updates be handled? And what about security and privacy and malware and curation and content moderation?

As for the creators of these apps, companies and individuals alike, what will change for them? Can they distribute their apps in multiple marketplaces simultaneously? And which system APIs (“Application Programming Interfaces”, the dialects that software components use to communicate with each other and with their host operating system) will be available to developers of independently-distributed apps? Will these apps need to be digitally signed, and if so, who is the signing authority and what standards must these signatures adhere to? Will the prevailing system of special app “entitlements” persist, and if so, who grants these entitlements to supplicants, and what appeal process is available to rejectees? And what about oversight and taxes and piracy and local regulatory compliance?

There are many outstanding questions, and no concrete answers at this time. The picture will clarify itself in the coming weeks and months, as iOS is updated to remove its blocks on installing third-party applications. In addition, the third party app marketplace vendors and aspirants will need official published documentation on the MobileInstallation framework APIs that are used by iOS to install and update applications. All of this will need to be available well in advance of the March 6 deadline, as the initial attempts at compliance are likely to be found lacking.

This is the first part in a series leading up to March 6, 2024 that will discuss the changing landscape of mobile software marketplaces, with a focus on free software and digital public goods. My name is Marc Prud’hommeaux and I’ve been programming computers for 40 years. I’ve written all manner of apps, great and small, for the iPhone App Store since its inception in 2008, and before. I recently created the App Fair Project to nurture and maintain truly free software for the devices people use everyday. You can reach me at marc@appfair.org.

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