They are made by connecting multiple smartphone circuit boards to a motherboard, and are used to generate interactions on social media such as likes, views, comments, and shares.
Hoang Trang was surprised to see over 20,000 followers in the Facebook account of an online business owner. Some of the posts in the account had thousands of likes, but most of the posters were not on the friend list of the account. Their profiles only show an avatar, without any content in them.
It is not rare to see the number of follows, likes and comments exceed the number of friends an account actually has.
"Except for controversial content that attract people’s attention, when ordinary accounts, meaning those belonging to people not famous or popular, have a very large number of likes and comments for mundane content, the interactions might have been generated from third parties," Hoang Nam, an online marketing expert in HCMC, explains.
"The use of bots to create virtual views and likes has been eradicated by platforms and has not been operational for a long time, and so many people come to phone farms."
He says the likes generated by phone farms are done using hundreds of smartphones, meaning they are real interactions, allowing them to evade platforms’ scrutiny.
Besides Facebook, people are now using phone farms to generate interactions also on TikTok and YouTube, increasing their number of followers and making their accounts more attractive for sales and advertisements, he says.
Phone farms are thus becoming more and more popular, he adds.
Nguyen Duc Hung, who operates a phone farm costing VND1 billion (US$41,000) in Quang Ninh Province, says: "Prices for different services will vary depending on whether you want to increase the number of likes or views."
The lowest rate to generate 50 likes on Facebook is VND2,250, but the more likes a customer wants to generate, the better the prices become.
For videos, 1,000 views on YouTube cost at least VND150,000, depending on how long the videos are, he says.
"Prices for Facebook and TikTok are cheaper since their algorithms are not as tough as YouTube’s."
Hoang Son, who operates a phone farm services in Dong Nai, says he offers lower prices, only charging VND3-4 for a Facebook like and YouTube and TikTok view.
He receives around 10-15 orders a week ranging from a few hundred thousand to dozens of millions of dong, he says.
"Those who come to me often have newly created accounts that need to have quick interactions or need them for personal reasons. Even artists, influencers and celebrities come looking for my services."
Generating comments and conducting seeding campaigns are trickier, and so cost more.
Minh Hai, who runs a phone farm in Nghe An, says a seeding campaign can cost millions of dong.
However, Nam points out that since interactions generated by phone farms do not come from real people, in the long run issues related to brands and business results can crop up, which can affect the business should social media platforms figure out what was happening.
"There are brands hired for advertisements for big money, which guarantee high numbers of interactions but in fact do not reach many people."
Many people also have an online shopping habit of looking at the number of interactions and reviews, making them susceptible to shops with low-quality products that buy virtual interactions and pull the wool over their eyes.
Son says fake accounts are frequently sniffed out by platforms and put on a black list, but each time new accounts are created.
The software used to operate phone farms are also constantly updated to evade such detection, he says.
"These processes are not difficult.
"The software used to create accounts are mostly developed within Vietnam to adapt them to social media platforms in the country, but they cost a great deal. Some parties look for Chinese software and modify their algorithms."
Phone farm operators are aware that they are indulging in borderline social media fraud.
"I am doing things that social media does not allow," Hung says.
"However, there is high demand in the market and the act is not illegal."
At a press conference last month an Authority of Information Security official said phone farm devices are not prohibited, but if they need to be regulated there would need to be new standards and procedures.
"We are aware that social media platforms are concerned with the issue."