How does Apptimize \ Optimizely work on iOS?

I'm trying to figure out a few things about the implementation going on "behind the scene" for manipulating UI elements on the fly, straight from the web console on Apptimize or Optimizely.

More specifically, I want to understand the following:

1) How does the client code (iOS) send the view hierarchy to the web-server in such a way that when you choose any UI element on the web dashboard it immediately shown on the iOS client?

I saw FLEX for example, and how it manage to get the view hierarchy, but I don't understand how the iphone client "knows" which view is picked in the web dashboard.

2) Moreover, in Apptimize I can choose any UI element from the web dashboard, change its text or color and it will immediately change in the app. Not only that, without adding any code, just by having the SDK.

The changes I make (text, background color, etc) will remain for all the future sessions of the app. How can this be implemented?

I'm guessing they are using some sort of reflection, but how can they get it to work for all users and for all future sessions? how does the client code find the right UI element? and how does it work on UITableViewCell?

3) Is it possible to detect every time a UIViewController is loaded? i.e. get a callback on each viewDidLoad? if so, how?

See some screenshots below: