Why hasn't iMessage been blocked in China? Does apple run a special compromised version of it there, or has China simply not made banning it a priority yet, or is iMessage simply not as secure as we have been told?
Most likely Apple cooperates with the respective agencies as requested by Chinese laws. If not yet, they will have to start very soon or iMessage will also be blocked.
Are there any signs of Censorship on iMessage so far? Are terms that are known to be blocked on WeChat, QQ etc (e.g. 法轮功 / Falun Gong) still working on iMessage?