The comment made the original assertion that LGPL versions 2.1 and 3 differ in that the changes in 3 makes it incompatible with App Store, where 2.1 was not. That's a strong claim, and the onus is on that person to back it up.
If you're actually interested in LGPLv2.1/App Store compatibility, the issue is so well-discussed that you can turn something up by searching for yourself. This is not a cop out. A scenario where someone puts a claim out there, someone challenges it, and then the challenger is told, "well prove it's not true", is not the proper thing, and that's what your comment does. So I'm turning down your request on those grounds.
> The comment made the original assertion that LGPL versions 2.1 and 3 differ in that the changes in 3 makes it incompatible with App Store, where 2.1 was not. That's a strong claim, and the onus is on that person to back it up.
Where was that claim made? The question was brought up if the LGPLv3 is compatible with the app store and it was mentioned that LGPLv2 code is presently being distributed via the app store.
> If you're actually interested in LGPLv2.1/App Store compatibility, the issue is so well-discussed that you can turn something up by searching for yourself.
It actually is not. There are various different opinions with regards to the LPGLv2 compatibility with the app store but there has not been any definite (eg: the FSF mentioned anything) answers to this dilemma. In particular many of these discussions predate the current state of affairs with regards to iOS where dynamic linking is now possible.
> A scenario where someone puts a claim out there, someone challenges it, and then the challenger is told, "well prove it's not true", is not the proper thing
I don't remember making a claim. I precisely mentioned that from my understanding the distribution of LPGv2 software on the app store is possible judging by what is actively being done. Something that cannot be said for any other *GPL license.
In any case none of this has been challenged in court so any of this is interpretation of a license by random people on the internet with more or less credibility on the topic.
> have a couple of choices according to the license requirements […] You can keep your app closed-source, but you provide to your users all the object code of your application necessary to re-link your application. That means for example all the .o and .a files. Most people forget that this option is in fact available to iPhone app developers.
Spend two minutes to read the rest of the article. It's technically possible for anyone developing with iPhone SDK to satisfy the LGPL, but that's so trivial an observation that there's hardly a reason to mention it. Writing an app with the iPhone SDK and publishing it on the App Store are not the same thing. The latter is the point that we're discussing.
As mentioned earlier: [citation needed] on this please. There are plenty of apps using LPGLv2 libraries on the app store.
//EDIT: currently the Qt website under does not recommend a commercial license for mobile apps from what I can tell and the wiki page is very ambiguous: https://wiki.qt.io/Licensing-talk-about-mobile-platforms