Four railway stations in Wuxi, Jiangsu province, started offering e-card services on Aug 20, meaning passengers no longer need to buy tickets before boarding high-speed trains.

E-card service on the homepage of the 12306 app. [Photo provided to wuxi.gov.cn]
The four railway stations are Wuxi New District Railway Station, Wuxi Railway Station, Huishan Railway Station, and Jiangyin Railway Station.
After activating the e-card service on the Railway 12306 mobile app, the State-run train ticket booking platform, passengers just need to scan the QR code on the e-card service page to pass the gate machine and board intercity trains.
All stations along the Shanghai-Nanjing Yangtze River High-Speed Railway, including Jiangyin Station, also launched the e-card service on the same day, as well as reservation and ID card scanning functions for entering and leaving the station.
The e-card service can also be used on subways in Beijing as well as subways and buses in Ningbo.

"Scan QR code to board" icon on the page of e-card service. [Photo provided to wuxi.gov.cn]
How do you activate the e-card service on the 12306 app?
Click the "e-card service" icon on the app's homepage, then the "scan QR code to board" icon to fill in your personal information.
Source:en.wuxi.gov.cn
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