Cab riders can now officially hail a taxi with their smartphones, the Court of Appeals ruled yesterday.

The decision allows people to use two of the first e-hail programs, called Uber and Hailo, to find cabs in their area.

“This decision will allow our e-hail program to move forward and give New Yorkers another way to hail a cab,” Mayor Bloomberg said in a statement.

Livery groups believe it will undermine their business as passengers use the app to search for a yellow cab before calling a car-service company.