Determine at runtime if the application is running on mobile

Hello,

I'd like to know at runtime, if the current application is running in
web mode (in browser) or as mobile app.
Is there some kind of property that I can use?

I have looked at Capabilities class, but I'm not sure it helps. I see
that there is a "playerType" setting, but it doesn't seem to
differentiate AIR from AIR on mobile.

Thanks in advance,
Cristian.