If you’re looking for a public bathroom in China, sometimes all it takes is just a whiff.

“Street-level public toilets in China are common, many detectable by the nose before they are seen,” reads Frommer’s tourist guide.

“Over the last decade the capital has made its toilets less of an assault course of foul smells and primitive appliances,” says Lonely Planet’s entry on Beijing. “But many remain pungent.”

Still, when nature calls and you’re not close to a bathroom -- perhaps technology can help instead.

The City Toilets app lets users locate toilets within a 1.2 mile-radius.

Since they launched in November, a toilet-finding app and a related WeChat Mini Program have helped more than 100,000 people locate restrooms throughout the country, according to Chinese state media.

The system, called City Toilets, was launched by the Ministry of Housing and Urban-Rural Development on World Toilet Day last year. The database is said to include at least 190,000 public bathrooms in more than 210 cities, with details such as whether toilet paper is available.

Users can even submit new toilet location entries and give feedback on a toilet’s condition. While the app is only available in Chinese now, officials say they’re working on an English version.

In a three-year nationwide campaign dubbed the “toilet revolution”, Chinese president Xi Jinping has been calling on cities to improve their public bathrooms. Tens of thousands of toilets have reportedly been refurbished since 2015, with thousands of new ones being built.

But some say bad bathroom etiquette remains a problem. For instance, there have been reports of toilet paper being stolen from public bathrooms at Beijing’s popular tourist spot Temple of Heaven. In response, facial recognition scanners were installed on toilet paper dispensers: The same person can only take 23 inches of paper every 9 minutes.

A man uses a facial recognition-enabled toilet paper dispenser at a public toilet at Beijing’s Temple of Heaven on March 21, 2017. (Picture: AFP Photo)