Mobile apps are making garbage collection more efficient and eco-friendly. Hou Liqiang reports.

Editor's note: In the wake of new regulations to encourage trash sorting across Shanghai, this is the first of two stories focusing on the central government's efforts to introduce the practice in Beijing, before expanding it to other cities around the country.

Lin Ming used to spend most of his working day riding a tricycle through Beijing's streets and alleys, bellowing "waste collection" at intervals. He described himself as a "guerrilla", who often played cat-and-mouse with urban patrol officers known as chengguan.

In 1997, the junior high school dropout joined his father in the capital to work as a junkman. The then-13-year-old had to try his best to avoid the chengguan, who impounded the garbage-packed tricycles of waste collectors like him, citing the fact that their activities were unlicensed and that the piles of trash they collected adversely affected the city's appearance.

However, Lin's cat-and-mouse working methods have been consigned to history since he became "incorporated into the regular collection army" by joining Tiantianjie, a garbage-recycling company. The veteran still collects waste, but instead of hawking for trade, business is just a click away.

Holding his smartphone, the 35-year-old waits for orders from an app called Lumao, literally "green cat", launched by Tiantianjie in 2015.

Residents of Donghuashi, a street in Beijing's Dongcheng district, and nearby Temple of Heaven Street can use the app to call the company's employees simply by clicking a button on their phone.

The central government is making unprecedented efforts to promote garbage sorting, but that has had the unforeseen result of social media platforms being inundated with people complaining about the difficulty of identifying the categories various types of waste fall into.

In response, companies such as Tiantianjie are offering viable internet-based solutions that are moving garbage-sorting programs forward by saving residents the trouble of sorting garbage themselves, and thus encouraging their future participation.

The onus on residents has been greatly reduced, because after selling their recyclable waste to companies such as Taitianjie they only have to dump their kitchen leftovers in specially designated trash cans, while other waste goes into specific bins in the community.