Quick response codes, or QR codes, have been introduced to 153 Shanghai buses on seven routes.

The move is part of a trial designed to allow passengers to check the whereabouts of buses and their expected arrival times.

The codes are expected to cover the city’s 580 bus routes by the end of the year, according to Shanghai-based news portal eastday.com.

Information, including a bus routes map, license numbers of buses and a timetable, can be accessed by scanning the QR code, a type of two-dimensional code, at bus stops by using a smartphone.

Although some users complained about receiving incorrect information after using the system, Shanghai Ba-shi, one of the city’s main bus operators, said it is only a trial run and that by June, when the trial is over, the service is expected to be introduced across the city.

Last year, the tourism authority in Hangzhou, the capital of Zhejiang province, started distributing packets of free tissues carrying quick response codes and linked to walking tours for visitors.

The QR code system is popular due to its quick readability and large storage capacity compared with standard barcodes.