Who do you tip? There's the obvious: waiters, bellhops, valets. There's the not so obvious: Uber drivers, nail techs, tattoo artists. And there's even the just-don't group: Plumber, grocery store ...

Hi. Yeah, we've been seeing more and more digital kiosks prompting us to tip on everything even to go and take out orders, which used to be tip free. And now you're wondering, what should I be tipping ...