Catching a taxi now moves one step further away from the analog tactic of waving your arm in the air and hollering “Taxi!” Back in July, Yellow Cab of Austin instituted use of the “Hail A Cab” app for all Apple devices and will follow with one for Andriod phones next month. The app allows taxi riders to locate nearby cabs, hail one with a push of the button, and then track the cab in real time.