"Starting a business with 0 dong from Peace Network. Having an opportunity like Pi Network, why not try it?," an account named Ngoc Van posted on a Facebook group about blockchain with more than 100,000 members, with instructions to download an app with pronunciation like Pi Network. He also spammed comments on many other groups with similar content.
Ngoc Van said in the past month, he has "recruited" about 100 members to "mine" virtual currency.
Not only Peace Network, he also installed a series of similar applications such as Rubi, StarCoin, LGBT Network, and BNP Network.
"Compared to Pi, participating in a new project brings more opportunities because the amount of mining is more. Maybe some projects will bring real money," Ngoc Van said.
"As long as one or two of the projects go public, I can make some money. Otherwise, I have nothing to lose but a little time to spend every day," he added.
Cryptocurrency mining applications have appeared, disappeared and reappeared.
According to the administrator of a blockchain group with 200,000 members on Facebook, the number of spam posts about cryptocurrency mining applications has increased day by day over the past few months, and they have had to use filters to block similar content.
"Every day, dozens of such posts are submitted but not approved," the administrator said. Compared to the craze two years ago, the applications are now more diverse, showing the expected amount of money earned if cryptocurrency mining projects are listed on digital currency exchanges in the future, assigning more tasks for users besides taking attendance.
Some apps even have white papers and development roadmaps. The apps support web, iOS and Android operating systems.
However, apps are basically the same way the Pi Network works. Users need to download the apps, then register, enter the referral code and "take attendance" every 24 hours.
The Rubi app was released in May and now has over 100,000 downloads, a white paper but a vague development roadmap.
"New apps are made professionally and methodically, not as simple as before, making more people trust them," commented Giang Nam, a cryptocurrency player for more than five years.
"With the mentality of losing nothing and fear of missing out, hundreds of thousands of people still install the apps and take attendance every day," Giang Nam said.
Among 10 such apps, most of which have between 10,000 and hundreds of thousands of downloads.
When installing, apps require providing a lot of important information, such as accessing location, reading and modifying the contents of memory, reading contacts, and accessing the network.
Previously, apps needed only users’ names and email addresses or phone numbers.
Currently, users are required to complete KYC (identity verification) from the beginning, including providing personal information, a photo of ID cards or passports, a selfie portrait, in addition to a phone number and an email address.
"This is a huge data warehouse that the people behind the apps are targeting. Users think they have nothing to lose, but in reality they face many risks due to the disclosure of personal information, from the making of forged documents to receiving scam calls or messages," Giang Nam said.
Vo Do Thang, director of the Athena Cyber Security Center, said most of cryptocurrency mining apps aim to collect user data.
"There aren’t any apps that give free money," Thang said, adding that "this trick is actually to entice users to provide personal information."
According to him, these data will then be collected to serve many purposes.
With the data, artificial intelligence (AI) can accurately classify each person, even make "a genealogy" of each person to see who they are related to, what they do, what their habits or hobbies are to perform tricks in a way that makes it difficult for the victims to detect.
"Before downloading any app, it is necessary to consider who is behind the app, how reputable it is. Avoid clicking and becoming a prey for bad guys", Thang said.
Philips Hung Cao, deputy general Director of cybersecurity company VinCSS, said KYC on many unlicensed cryptocurrency mining apps is not managed and supervised by the authorities.
If KYC is required, users should ask at least three questions: Is personal information protected under privacy laws and regulations? Is the information shared with third parties? If the personal information declared on the app is leaked and used for fraudulent purposes, who will be responsible for compensation? "With these three questions, unlicensed virtual currency mining apps certainly cannot meet and users will understand themselves that they should not do eKYC or KYC," he said.
Another source of revenue for cryptocurrency mining apps on smartphones is advertising. Most the apps include ads, forcing users to see before accessing a feature.
In addition to the risk of information being stolen, experts say such apps also waste time, take up phone resources, and create a feeling of "virtual hope" for participants.
After five years of being present and receiving many expectations, money earned by using cryptocurrency mining app Pi Network is still worthless now, and the team behind it is almost silent.
Pi Network has been under investigation after critics said it lacks the transparency associated with blockchain, and could be used for nefarious purposes like fraud and data collection.
Cryptocurrencies are not recognized as a legitimate means of payment in Vietnam whose central bank has warned that owning, trading and using cryptocurrencies are risky and not protected by law.