Air based documentation
Titanium based documentation
Printable View
I've found the local web documentation ( coming with the ExtJS package ) to be the best solution . Thats because the browser page-search, which is often extremely usefull.
AIR don't have such ( don't know about titanium ).
Just my bit of thought about those documentations.
Honestly, I don't download any of that mess. just the SDK/API and i'm good to go.