The agency is testing a mobile ticketing program on the Pascack Valley Line and the Meadowlands Rail Line.
Passengers can use their smartphones to purchase one-way tickets and monthly passes for travel on Pascack trains, as well as between New York's Penn Station and the Meadowlands Rail Station for special events.
N.J. Transit customers must download the free My Tix application at the App Store for iOS phones and the Google Play Store for Android devices.
The Pascack Valley Line was chosen for the pilot program because it has a smaller customer base and more consistent rail crew and equipment assignments.
N.J. Transit will evaluate mobile ticketing after the three-month test period.