According to the FSF, the distribution of a binary computer program which substantially relies upon GPL libraries is considered a derivative work and would require you to abide by the terms of the GPL license.
Similarly, an iOS app which substantially relies upon (and must be compiled with) Apple's libraries in order to work is subject to whatever the terms Apple includes in their software license. Of course Apple isn't requiring code to be open source like the GPL. Apple could choose whatever terms they want. It would be perfectly within Apple's right to require a revenue share for use of those libraries—say, the Metal graphics APIs—just as Epic Games does for the use of Unreal Engine libraries.
Therefore it's entirely reasonable to imagine that if third party payment gateways are permitted, Apple could still organise things so that they are legally entitled to a percentage cut of app sales. Again, just like Unreal Engine.
To the people down-voting this, I realise that my post espouses a controversial opinion for Hacker News. But could you please explain what you disagree with?
> which substantially relies upon GPL libraries is considered a derivative work and would be a GPL violation if it's distributed without source code.
I didn't vote either way, but I'm not sure that this is the way the GPL works. As I understand it, you can distribute only binaries as long as you supply _on request_ the source code. FWIW the link to the GPL reads as quite tenuous and what I would guess the downvotes were for.
> Similarly, an iOS app which substantially relies upon Apple's libraries in order to work is subject to whatever the terms Apple includes in their software license
Yes, they are free to do what they want, barring regulation. Which is what this is. Deliberately loopholing around the legislation is an option, but a risky manoeuvre that might just invite more legislation.
Thank you, I did err in how I described the GPL. I have edited my post to correct this.
> FWIW the link to the GPL reads as quite tenuous
The link is that any developer—whether they're Linus Torvalds or Apple Inc—should be allowed to choose the terms in which they release their copyrightable works into the public.
• One developer could choose the GPL.
• Another developer could choose a license which requires a flat, one-off fee.
• Yet another developer could chose a license that is free up front but mandates a revenue share under certain conditions, such as Epic Games does with Unreal Engine.
In all instances, it is copyright law which enforces these license terms. So if you like the fact that Linus can distribute Linux under the GPL, you must also accept that some other company will have the right to distribute their software under their license.
> To the people down-voting this, I realise that my post espouses a controversial opinion for Hacker News. But could you please explain what you disagree with?
The issue is not that your argument is controversial. It's that it falls flat because it's based on an incorrect assumption.
> Apple could choose whatever terms they want. It would be perfectly within Apple's right to require a revenue share for use of those libraries
No they can't.
There are a broad set of laws restricting how companies can or can not do business. These laws severely limit the terms Apple can set. Laws restricting anticompetitve behaviors would be part of this set, same for the new regulations in South Korea we are currently discussing.
My apologies, when I said "whatever terms they want" I was being somewhat hyperbolic, even if I do think the spirit of the sentence is clear when read in context. Obviously terms of any such license cannot violate law.
Are you suggesting that Apple charging developers a percentage-based license fee for use of their work is unlawful anywhere, under any law current or proposed?
> Are you suggesting that Apple charging developers a percentage-based license fee for use of their work is unlawful anywhere, under any law current or proposed?
The crux of the discussion generally focus on the parts of the contract preventing developers from using competing works in addition to the fees. That seems to fall squarly into your "whatever terms they want". And yes, I do personaly think there is a case to be made that Apple licensing terms are anti-competitive, an opinion which seems shared by the EU’s competition chief.
Your opinion seems to be that Apple could just stop charging a fee for using the App Store and charge it for the use of a different but similarly unavoidable part of the system instead. But that's merely a technicality. It doesn't fundamentaly change the question.
Microsoft Visual Studio was not free in the past. And even now free version is limited. I don’t see it different from hypothetical paid Apple library as long as there are other ways to write software for the given platform.
Is your argument that anyone who builds a device which runs software is required to ensure that an entirely free way to develop software for it exists? That makes no sense.
Tell that to Nintendo. Sony. Microsoft. Canon. Nikon. Garmin. Alpine. Pioneer. LG. Samsung. Volkswagen. Hyundai. The list goes on. Software is all around us. The traditional general purpose computer platforms are the exception, not the rule.
I can see the argument by analogy to GPL, but I don't think this is about software licensing in practice.
It's about control. Apple control how and which apps get to users, and use this control to impose terms, license or otherwise, that maximize their revenue and other goals.
Perhaps you are right that Apple could reengineer the business model to charge software licensing fees rather than payment service fees. They could also make the 30% a publishing fee. There are probably other options too. You can do a lot when you have the power that they have.
That said, practicalities matter. If you want to take a cut of a large number of apps' revenue... the place to do it is point-of-sale. Take your cut before app devs get theirs. If payments go to app developers via some other payment system, Apple now needs to chase down a revenue linked licensing fees from 2m apps... that's messy and impractical. They don't know how much they are owed, for one thing.
Similarly, an iOS app which substantially relies upon (and must be compiled with) Apple's libraries in order to work is subject to whatever the terms Apple includes in their software license. Of course Apple isn't requiring code to be open source like the GPL. Apple could choose whatever terms they want. It would be perfectly within Apple's right to require a revenue share for use of those libraries—say, the Metal graphics APIs—just as Epic Games does for the use of Unreal Engine libraries.
Therefore it's entirely reasonable to imagine that if third party payment gateways are permitted, Apple could still organise things so that they are legally entitled to a percentage cut of app sales. Again, just like Unreal Engine.