Picture used for representational purpose only NEW DELHI: The final phase of trial of contactless ticketing system will begin in the around 3,000 cluster buses run by the Delhi Integrated Multi Modal Transit System (DIMTS) through the 'Chartr' app from Monday, a transport department statement said. The trial of the app is already underway in all 3,760 buses operated by the Delhi Transport Corporation (DTC), it said. Approximately, four lakh tickets have been booked using the app so far. The pink tickets for women passengers, who travel free of cost in public transport buses, comprise 67 per cent of the total tickets booked through the app, it said.