Cash is at times hard to find in today’s China, where QR codes are in use at virtually all shops and roadside stalls throughout the nation.

Nowadays, a quick scan using the WeChat or AliPay app on your smartphone is all it takes to make an instant payment, saving you from the hassles of tending the exact amount or ending up with a pocket full of filthy coins.

Now Chinese tech giants want to make that process even simpler: without even the need for a smartphone, all you might need to do is glance at a camera before you are free to go with your shopping. This could even be of particular use when your phone is running out of power or you find yourself somewhere with poor cellular coverage.

Alipay has recently released its latest facial scanning payment product, Dragonfly, which slashes access and installation costs for merchants by 80% compared with the previous generation.

Seeing the huge potential in facial recognition payment, Tencent’s WeChat Pay and UnionPay, the other dominant players on the Chinese market, are also gearing up to roll out their solutions.

Juts like Apple’s Face ID, a facial recognition system developed for the iPhone and iPad Pro, similar systems allow biometric authentication for making payments.

Cameras, sensors, algorithms and processing speed are the keys to a system’s effectiveness. One sensor projects a grid of small infrared dots onto a user’s face, and a camera reads the resulting pattern and generates a 3D facial map and compares it with the registered face using a secure subsystem, which can recognize faces with glasses, clothing, makeup, and facial hair, and is even able to adapt to changes in appearance over time.

Xue Hongyan, director of the internet financial center under the Suning Financial Research Center, told the Beijing Business Daily that facial payment could free users from their mobile phones and elevate their ease and experience when shopping.

However, just as when QR-code-based payments set out to replace hard cash, some are skeptical about the privacy and security of the pay-with-your-face fad.

While settling a bill is as easy as a simple glance, information about one’s face, gender etc is collected by a vendor and payment facilitator, which can be easily leaked if not managed properly.

Risk of false positives are also a concern, and questions are being asked about what if someone wears a convincing facial mask of another one to make the victim to pay for the bills? And how about twins?

For those who are willing to pay via facial recognition but have doubts, combined verification such as setting up an additional passcode is recommended to beef up the security of their bank accounts.

“Millennials always love to embrace new technologies, but there are risks. But for those conservative types who stick to cash and think it’s the safest way, there are also risks of fake banknotes or simply losing your wallet,” noted a participant on a forum managed by the People’s Daily.