Uber app is just too fast to be good. Cab bookings are misfired. Even when a user is just exploring the app and is not really ready to book a ride. We get a call from the cab driver. Cab rides get booked even before you could select your destination. Then the cab drivers informs you to cancel that ride (which you anyways did not actually intend to book). If you fail to cancel within 15 minutes, you have to pay a cancellation charge (gets added to your next ride)
Uber app must have a "confirm" button so that the ride is booked only after that confirmation