Implications of APSL

[Dmitry.Skiba]

Let's discuss something complicated -- implications of the fact that
Itoa uses several libraries that are released under APSL (objc4,
CoreFoundation).

Here is the text of the license: http://www.opensource.apple.com/license/apsl/

It seems that every app using Itoa should include a section in About
dialog that would state usage of modified APSL code and contain "...
information on how and where to obtain such Source Code".

Anything else?

Overall APSL seems ok, but given the recent lawsuits by Apple it is
interesting to discuss on how Apple can stop people from using their
open-source code -- they won't be chasing every single person who
cloned a github repo, right?

[Eric Wing]

I'm surprised to see that these haven't been relicensed under Apache.
Apple had relicensed a lot of their projects to Apache because they
wanted people to use their stuff but legal departments from most
companies were unsure of how to deal with yet another open source
license. Apple moved to Apache from feedback that most companies were
already comfortable with Apache.

As for APSL, I think most, including FSF consider APSL 2.0 'free
software'. I don't see how "Apple's lawsuits" have anything to do with
people using their APSL code.

But for itoa, I think the bigger problem is that you have some GPL
licensed components. According to FSF, APSL is incompatible with GPL.
I forgot the reason, but I think it is related to the patent clauses
(which I think is similar to why Apache used to be incompatible with
the GPL). Specifically, making itoa-main GPL will be incompatible with
Core Foundation and objc4-runtime (because I'm presuming these must be
linked). So you do have a problem here.

I'm not sure what your goals are, but I making any component GPL will
deter adoption of itoa. Most people doing iOS development are in
commercial/proprietary development and iOS forbids dynamic linking to
3rd party libraries which rules out both GPL and LGPL. So most iOS
developers avoid (L)GPL. These are the people most likely to be
interested in something like itoa, but if something as important as
UIKit is under the GPL, most aren't going to give it a second glance.

[Dmitry.Skiba]

Wow, I didn't know about Apple relicensing their code. Nice move.

As for APSL -- there are those termination clauses, especially "patent
infringement" subclause: "(c) automatically without notice from Apple
if You, at any time during the term of this License, commence an
action for patent infringement against Apple;". Given that Apple owns
several basic software-only patents (like the ones they used to sue
HTC), this can be a problem. Or not. Maybe I demonize Apple too much.

As for GPL vs APSL - good catch. Indeed, APSL code can't be used with
GPL.
The thing is that all GPL code in Itoa is in fact doubly-licensed,
under GPL/Commercial licenses. I also have plans to grant contributors
rights to use Itoa in commercial products, and the contribution
doesn't need to be done to GPLed projects, any Itoa-related project
will do. I'm going to blog about all that soon, and update project
pages.

Returning to the licenses, it seems that Apache/APSL both require
notices on "About" screen. I'm thinking of implementing generic Itoa
copyright screen which can be easily integrated in the end
applications, and will contain all needed information.