How to Call a Taxi/Cab in "GTA 4"

The "Grand Theft Auto" games are known for vast worlds that expand over several islands. "Grand Theft Auto IV" is no exception. As you play, you will explore the neighborhoods on the islands of Broker, Bohan, Dukes, Alderney and Algonquin. To speed up game play, you can take taxi rides across town. You can either choose to call your friend Roman for a ride or take advantage of the hundreds of taxis around Liberty City. 

Steps:
1.Complete the second mission of the game, "It's Your Call," to receive your cell phone.
2.Hang out with Roman until you reach the 60 percent "like" level. This will unlock the "Driving Mr. Bellic" milestone. You can now call Roman for a taxi ride.
3.Press "Up" on the directional pad to open the cell phone menu. Select Roman's name from the contact list, and then select "Taxi."
4.Wait for a taxi to arrive. Early in the game, a driver will pick you up in an Esperanto. Later in the game, Roman's taxi becomes a Cavalcade.
5.Whistle for a cab if you do not want to wait for Roman's taxi. Hold the "L1" trigger to whistle, and a taxi will pull up to the curb. Hold the "Triangle" button or "Y" button to enter the cab.

while you saw a taxi Hold the "L1" trigger to whistle