I would add that it's "doing nothing important". Like when someone asks: What did you do today? And the german answer is just "Nix" ("Nichts", aka. nothing important)
It sounds like what we call "timepass" in Indian English, and also loan in other Indian languages. It's a very popular word and has made it into the Oxford English Dictionary as well.
And just like 'Niksen', that too is without deeper intent. You just hang. Closest I can come in English is probably 'idling about'.
You do or don't do stuff. Your brain is meandering about. You don't really care about time passing.
It's definitely an art form, most people get bored after a while - true masters can do days on end ;)