There is no effective way to rein in individuals' carbon emissions, but rewarding green living can provide motivation, said Nie Bing, who heads the app development team of a Guangzhou-based state-owned company under the Ministry of Industry and Information Technology.

The team is testing the app at a Guangzhou community, with hundreds of registered users, Nie said, adding that rewards are currently given for using public transit, waste recovery, as well as saving water and electricity.

Liu Jia, who has been testing the app, has enjoyed discount meals at a fast food restaurant near his office since he started collecting points for his subway commute and walking every day.

"With the bonus, green consumerism is not only a spiritual goal for me, it also makes financial sense and encourages me to stick to my lifestyle more easily," said Liu, an environmentalist.

A guide on the program issued by the provincial development and reform commission along with the directive suggests the governments of pilot cities mobilize businesses to offer discounts that are more generous than ordinary promotions to "green points" owners.