I know it is a trivial function, but is there an option in Android Studio to open project folder into a file explorer (from AS)?
p.s. It is always possible to navi
You can press ShiftShift, or go to Help->Find Action... type Reveal
and on Mac OS X you'll get "Reveal in Finder" action. On other operating systems the action may have different title but it should be there. You can also map a shortcut for that action in Preferences->Keymap.
I found The answer myself: do as follow in Android studio
Yes, you can simply click left mouse button on open file tab with Ctrl pressed.