Travellers in Beijing can now use a QR code on their smartphone as a ticket to ride the subway, according to a report by Beijing News.

Passengers can download an app called RuubyPay that generates a QR code ticket that can be read using a scanner built into the subway turnstiles.

The QR code scanning app can be used on any smartphone running iOS or Android that is connected to the internet, according to Sina.com. Tickets can be paid for using a linked bank, Alipay, or JD Finance account.

The new system is an improvement over previous efforts to allow travelers to use their smartphone to ride the subway in Beijing.

Passengers using an Android smartphone that incorporates NFC technology, and is linked to a mobile wallet, have been able to use their phones to scan in and out of the subway since August last year. But the limited number of Android phones that worked with the system, and the inability of iPhone owners to use it, limited its take up.