When you book a ride in the app, it does tell you how much you will pay. It does charge you through the app. It is possible your friend was travelling in a high traffic time where the surge charges more. You should go to green light hub and talk to someone in person and make sure this was on the up and up. If not they will help you resolve this.
It requires a card or uber prepaid card with enough cash on it before the app will even send your request to a driver.
Before coming where
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