To summarise, any iOS app, even if its source code is fully disclosed,
cannot possibly grant all of its end users the ability to reproduce
the executable, for three reasons:
1. It requires a Mac, which is not the same operating system as iOS,
2. It requires a subscription to the Apple developer program, without
which it is impossible to test on a real device,
3. It requires explicit approval from Apple, without which it is
impossible to distribute to others.
On my point 3, it may seem like I am being overly picky. (Surely it is
sufficient that the user can modify the program and test it without
the ability to distribute their modified changes to others?) But no --
point 3 is in fact essential in the Free Software Foundation's
definition of free software. From
https://www.gnu.org/philosophy/free-sw.html, the final of the "four
freedoms":
"The freedom to distribute copies of your modified versions to others
(freedom 3)."
This last point is one of the main reasons the (L)GPL was written in
the first place.