China used to be called the "kingdom of bicycles," and while cars have taken over in a major way, the growing popularity of bike-share apps maybe assign two-wheelers are making a comeback.

The bike-share color revolution of yellows, oranges and blues is a welcome sight in drab and dusty Beijing.

Young and old are enjoying the convenience bike sharing provides, all it takes is the quick scan of the bikes' QR code and you are off.

"After I get off the metro, I usually have to walk another kilometer or two, so I'll grab a bike share and go. It's less stressful."

"Now, when we're riding home from work, especially in the evening, when it's not as rushed, it feels like we're reliving the past."

But the soaring popularity of bike sharing is giving local governments major headaches.

Illegally parked bikes are clogging streets and metro exits overwhelming the authorities.

"Since the Lunar New Year, the number of bikes has been growing rapidly.
At least 10,000 bikes have been added to the streets (of Daxing) since then, and we've collected about a third of that total."

China's two biggest operators, Ofo and Mobike, have already deployed more than 3 million bikes in scores of cities across the country, and the numbers are growing.

As complaints increase about the bike share takeover city streets, some are taking action, becoming bike hunters.

Gao xiaochao uses his lunchtime to find, report and move illegally parked bikes.

"Bike hunting is like a game, a hobby, a way to get some exercise, it's like a new way of living.

Sometimes, I spend two to three hours looking for illegally parked bikes and it's just like taking a walk."

Bike sharing has benefits to transportation break and the city's notoriously smoggy air, it is waiting for passionate supporters like Gao.

But as complaints grow, competition gets increasingly cut-throat, they hope more is done to improve their service instead of just flooding the streets with bikes to edge out competitors.