Whatever works for the task at hand. Flash Player did a lot of stuff.
For watching videos HTML5 seems to be the default these days. In fact HTML5 can run chat rooms in a browser window too, and I'm not quite sure why Robo didn't default to it.
For CC it seems we are running Adobe Air. Install it on your Windows computer or phone and run the CC application inside Adobe Air and it should work.
For Linux users... good luck, you'll need it.