In an Australian first, customers can choose the right train carriage based on real-time train occupancy data.
Using the average weight of a NSW train passenger, the app determines the occupancy of each carriage as the train doors close.
The information will be available for more than 600,000 customer trips on Waratah trains every day.
Premier Gladys Berejiklian said customers have had access to bus occupancy data since 2016.
“Now train customers can see how full their train is before it arrives,” Ms Berejiklian said.
“Transport is no longer just about infrastructure but also about embracing technology to provide the best services possible for our customers.”
Transport and Infrastructure Minister Andrew Constance said letting customers know which services might be full or which carriages still have seats will make commuting easier and help ease congestion.
“For customers who commute home from Wynyard to Penrith, for example, getting a seat can be a major factor in deciding which carriage to board,” Mr Constance said.