HOUSTON -

A new transportation service is expected to launch in Houston Friday.

The iPhone and Android app is called Lyft. If you need a ride you open up the app, and a driver gets a message and heads your way.  

Curtis Rogers, of Lyft, said, "Scenario is you're out on a Friday night and parking is bad or you don't want to be driving afterwards, Lyft is a great way where you can press a button. The app knows where you are."

Lyft said it would send a car with its signature pink mustache on the front. The company said it could be just about any car as long as it's 4-door, has room for four passengers and is Lyft-approved.

The company said what you pay for the ride would be up to you through what it called a "donation" made through the app. 

Rogers said, "At the end of the Lyft, we will recommend a donation amount for you based on the time in the car and the distance that you went."

But the city of Houston said for now, companies like Lyft and its competitor, Uber, cannot legally operate here. 

Mayor Annise Parker said, "There's some working girls that work the streets of Houston that say 'We're legal because it's just a donation'. I'm sorry. We will enforce our ordinances." 

The city requires vehicle inspections, permits and licensing of drivers for "work for hire" transportation like taxis. Parker said the city could change the ordinance, but that has not happened. 

"If they start operating, we will shut them down," said Parker.

Lyft plans to launch its new service on Friday with a kickoff party at Hughes Hanger on Washington Avenue. Lyft said rides will be free with no donation required for the first two weeks. 

Houston's City Council is set to talk about possible changes to city laws next Tuesday. Any changes and a vote could come sometime after that meeting.

Uber said it launched in May 2012, with more than a million rides since in 20 cities. It said passengers sit in the front seat. It claimed it implemented safety measures beyond taxis or limos.