All these apps are excellent, but one problem I see is that when...

All these apps are excellent, but one problem I see is that when I call for a Taxi, am I going to try to get one of an application that may have 10% of cabs that might be on the other side of town, or the one that has 90%. Which one is more likely to get the cab to my door Quickest?

Secondly, picture the Saturday night cab line, are the punters going to be allowed to hunt for the taxi they want so as to pay via phone? or are they going to jump into the cab they can get and pay by card?