Although the novel coronavirus outbreak has largely been controlled on the Chinese mainland, people still need the health code app, which records their recent whereabouts, to gain access to most public places, including public transport.

Only green code-holders are allowed to enter public sites, like a supermarket, a bank and a hospital, as long as their body temperature, measured on the spot, is below 37.3 C.

A green code means its holder is not likely to have been in close contact with people infected with the novel coronavirus over the past 14 days; a yellow code means its holder might have been in close contact with infected cases and should be quarantined for 14 days for medical observation; a red code means its holder is possibly infected with the virus and must immediately seek treatment at the nearest clinic.

The health code app is based on big data. It combines data from the transport, public security and public health departments, and its reliability has made it a useful tool for containing the contagion.

But there are some people, mostly elderly citizens, who do not use smartphones, on which the health code app works. That means they will face problems even if they are not infected and would have been green code-holders had they been using the app.

Many social media users recently expressed sympathy for a senior citizen who is seen in a video losing his cool at a subway station in Dalian, Liaoning province, for being unable to show his health code.

Reportedly, about 250 million people in the country lack the skills to use a smartphone or do not use one. However, they should not be left untended on the other side of the digital divide. After all, the government is duty-bound to guarantee them access to basic public services.

While bragging about how smart the cities are, the government should not forget that smartness does not discriminate against the elderly.

Although this is the information age, people still have a right to stay detached from it, and that right should be respected.