The reason I use Flash is to save development cost. Adobe AIR can help me distribute this app to web, pc/mac and mobile devices. I know HTML also works for these devices, but I am not familiar with HTML5.
If there are many people like this app, I will try to port it to HTML5.
If you want to launch anything in 2015 it's HTML5 or bust. If you know ActionScript, you know Javascript.
Instead of Adobe Air, use something like nw.io / node-webkit, or Github's awesome Atom Shell.
Throwing in my two cents: Atom Shell is now known as Electron[1]. Clever, eh?