Start-up Worldcoin advertises that people who authenticate their accounts with an iris scan would receive free cryptocurrency. Worldcoin claims to have sent scanning devices to people in 12 different countries. To preserve users’ privacy, after they join up by having their iris scanned, the image is encrypted and turned into a unique code, while the original data is discarded. The Worldcoin cryptocurrency is then distributed to users for free. Worldcoin has over 100,000 users worldwide and is adding 700 new ones every week. By 2023, the startup hopes to have 1 billion users.