United Airlines’ technology that helps connecting travellers make their flights is being expanded beyond a handful of initial test cities, USA Today reports

The ConnectionSaver system, rolled out first at Denver International Airport and then Chicago’s O’Hare International Airport, identifies flights that can be held for connecting passengers arriving on late flights and also provides customers (via the United mobile app) with directions on the fastest route between their arrival and connecting gates.

United announced that the service has now been expanded to Houston’s George Bush Intercontinental Airport and Newark Liberty International Airport, and will be added at San Francisco International Airport on August 6 and Dulles International Airport in Washington DC on August 13. More additions are on the way.

“Following the busy summer period, we’ll share details about our plans to expand the tool to all United line stations,” the airline said in an internal memo to employees.

United officials said that in its first four months of operation, ConnectionSaver prevented 14,400 travellers from missing flights, with connecting flights held an average of six minutes to allow late-arriving passengers to board.