I do not understand it. After a trip, it can be hours before the app finishes "processing the payment". The best it can then give is an "estimate", which sometimes changes over time. And the final result is still off, in my experience about 50% of the time! If it's not Uber overcharging the rider, it's them messing up the sales tax (I'm in New York, where a sales tax is deducted from our earnings). And it makes no sense - sometimes they deduct too much for the tax, yes, but sometimes they deduct too little! IT IS INSANE. THESE ARE COMPUTERS!