Author of this article is missing LGPL entirely. LGPL allows anyone to ensure that all changes to his code are published freely, but also allows packaging with commercial closed-source code into single downloadable file (unlike GPL).
On platforms that support dynamic linking this is easy to allow - just package the LGPLed library as a dynamic library the user can easily replace. On platforms that don't (e.g. iOS) it's harder, and I believe it's still 'gray' what's required in practise - or even if the requirement is possible to satisfy. Some will say if you supply object files so that the end user can relink, that's fine.
It's not "some will say"; supplying object files for your code and source for the LGPL library is specifically listed as an option in the LGPL itself.
[LGPL 2.1, section 6a]
Can an iOS user do that? I would not like to depend on saying "Yes" to a court.