Price can be much higher than a REAL taxi, depends on the greed of the driver. If the driver thinks he can get more than the app price he will cancel your ride and wait for the price to go up, maybe several 'cancels' later the price goes up 35 to 40% more than what the app originally quoted. A very shady pricing scheme that can easily exceed the price of a dependable regular TAXI.
I speak from real experience.

Who knows. Even drivers can't figure out the mathematical calculations. Alga rhythms ect. Robbing us blind.

They claim its Based on your pickup and drop-off locations. One thing to remember is not to engage in conversation with them(that's the scam) they want you to be soo relaxed that when your trip ends you will get out of the car and forget about asking what the ride cost.
In order for them to give you the amount the driver has to "complete" the ride on the phone.