Correction: This article has been corrected to say that Bluegogo only put hundreds of bikes on the streets of San Francisco rather than 20,000 as initially reported.

A rider cycles an Ofo bike past other dockless bikes in Beijing. Immensely popular in their homeland, China’s bike-sharing companies are now racing to expand abroad. (Shirley Feng/The Washington Post)

— To rent a bike in China, all it takes is a phone app, and any of the millions of bicycles scattered on sidewalks everywhere can be yours. No bike stand. No drop-off point. You scan a code, you ride, you leave and lock the bike wherever and whenever you’re done.

China’s billion-dollar bike-sharing revolution has already transformed the look and feel of cities around the country, with more than 100 million apps downloaded and billions of rides taken on many millions of bikes.

Now it is going global.

Last month, a Chinese company called Ofo made its first foray into the United States, delivering 1,000 bicycles to the streets of Seattle, with plans to expand nationally. From Italy to Kazakhstan, from Britain to Japan, from Singapore — Asia’s greenest city — to one of its most congested, Bangkok, Ofo and its main Chinese rival Mobike are on a breakneck race to expand across the globe.

Welcomed in many cities, but not by everyone, the companies are already encountering a backlash. Opponents have branded Ofo and Mobike a menace, a plague and a public nuisance.

Each of the two main Chinese companies has more than 7 million bikes in operation in over 150 cities, mostly in China, and each recently attracted $600 million to $700 million in new funding to finance their global expansions.

Bikes are typically fitted with GPS locators to enable users to find them via the app. Payment is minimal and made electronically.

Beijing, a city where bikes once ruled, has once again taken to two wheels, and most cyclists seem to use a shared bike these days. Greener and healthier to use, the bikes get commuters to and from public transit stations and discourage car use. They solve what planners call the “first-mile-last-mile problem,” helping people get from their homes to a bus stop, for example, or from a subway station to their final destination.

Dubbed “Uber for bikes,” they have proved much more popular than schemes based on docking stations. New York’s Citi Bike, with 10,000 bikes and 236,000 subscribers, is the largest operation in the United States. Compare that with Beijing, which has 700,000 shared bikes and 11 million registered users, nearly half the capital’s population. (Washington’s Capital Bikeshare program offers 3,700 bikes.)

Unlike arrangements based on docking stations in Washington and London, the dockless model doesn’t require government subsidies and is already spawning rival start-ups: California’s Spin and LimeBike narrowly beat Ofo to the punch in Seattle after the city pulled the plug on its subsidized bike-sharing program.

Ofo is now advertising on its LinkedIn page for a country head based in the greater New York area, while Mobike is advertising for jobs in Dallas/Fort Worth, Chicago, San Francisco and New York.

The explosion in users speaks to their success. But they are not universally liked.

A worker from the bike share company Ofo unloads new bikes on March 27 in Beijing. (Kevin Frayer/Getty Images)

In China, bikes clog sidewalks and pile up in unruly flocks outside subway stations, shopping malls, office buildings and road intersections. Unwanted or broken bikes are dumped by highways, in rivers and parks, on construction sites or under bridges.

Shanghai-based blogger Marc Milián calls them a “plague,” while locals have taken to social media to lambaste the “anarchic experiment” that is creating “a new generation of trash.”

Shanghai’s government has seized thousands of illegally parked bikes. It recently called for a halt on companies putting more bikes onto the streets and asked them to work faster to remove badly parked bikes.

Yet, in a country where the government puts a premium on controlling its citizens, Chinese officials have displayed a remarkably light touch with this booming new business. In guidelines issued last month, the State Council welcomed shared bikes as part of “the green urban transport system,” while urging local governments “to ensure rational allocation of bicycles and avoid excess supply in some areas.”

Unlike Uber, bike-share companies haven’t angered vested interests such as taxi drivers, but they may run into much stiffer opposition from regulators and citizen groups in the West.

In San Francisco, China’s Bluegogo dumped hundreds bikes onto the streets in January without permission. City Supervisor Aaron Peskin called them a “public nuisance” and threatened legal action against an “arrogant” tech company.

Writing in the San Francisco Examiner, Darcy Brown of the citizens group San Francisco Beautiful called Bluegogo a “rogue” company that was “bringing chaos to our public spaces” and posing a “threat to the beauty and livability of our city.” Bluegogo said the company has since pulled its bikes from San Francisco.

In Singapore, the arrival of 30,000 bikes met with mixed reactions, with some people reportedly calling them a “menace.”

In a sense, bike-sharing schemes are tests of the societies in which they are launched and whether communities can look after public goods.

In China, vandalism and theft have been a problem, and it is easy to spot bikes with broken locks, wheels removed or smart codes scratched off.

But that appears to have been trumped by people’s enthusiasm for all things digital, for e-commerce and anything that arrives through their smartphones — what Peking University professor Jeffrey Towson calls “their hyper-adoption of anything mobile, plus the almost uniform adoption of mobile payments in China.”

In Britain, vandalism initially blighted Mobike’s June launch in Manchester: Police reportedly recorded 20 incidents in just the first 10 days, with bikes thrown in a canal, and a video catching a youth throwing rocks in an attempt to destroy one of the supposedly vandal-proof bikes.

“That’s why we can’t have nice things,” one Mancunian commented on Twitter. “This is a real shame. I love those bikes — someone always wants to ruin stuff!” another commented.

Yet many more Mancunians enthusiastically embraced their “new toy,” said Chris Martin, ­Mobike’s vice president in charge of international expansion. There were even reports of people cleaning the bikes or jumping in the canal to fish them out.

The company has ruled out the approach taken by Bluegogo or Uber, and instead works closely with local governments before launching — giving them control over how many bikes should be supplied and time to issue parking guidelines.

“The Uber model is to ignore local government, subvert it, grow larger than can be controlled, and then afterwards ask for forgiveness and permission,” Martin said. “We very specifically chose to do the opposite.”

The companies hope to encourage better behavior by awarding users credits for reporting broken or illegally parked bikes — and demerits for correspondingly bad behavior. If your score drops too low, your next ride could become much more expensive.

Ofo began as a student project at Peking University; its 26-year-old founder, Dai Wei, now runs a company valued at $3 billion. No surprise that among Ofo’s first forays into Britain have been the university cities of Cambridge and Oxford.

The economics remain fuzzy, experts say: In China, short rides are free, and many users say they pay virtually nothing. But even with the cost of maintaining and replacing broken bikes, Dai says, Ofo should break even by year’s end.

Towson sees potential for raising revenue with advertisements on bikes, as well as a move to paid subscriptions. He’s also optimistic about the move abroad.

“What I love about these companies is the way they have exposed how inconvenient owning and/or renting bicycles has always been,” he wrote on his website. “Try convincing someone to buy a bicycle and store it in their apartment in Shanghai now.”

In Seattle, there are now 3,000 dollar-a-ride dockless bikes on the streets, and usage has crushed the old docking-station-based project, says Tom Fucoloro, editor of the Seattle Bike Blog. Nor have fears of chaos been realized.

“Everyone’s scared to death of these piles of bikes. I find that kind of funny — too many bicycles would be an amazing problem for a U.S. city to have,” he said.

“Almost all the bikes are parked out of the way, more or less properly, and if they aren’t, someone will just come and move them out of the way. Seattle’s kind of a rule-following town in that way and that’s playing out with the bikes.”

Shirley Feng contributed to this report.

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