Visitors consult about using of L'Oreal's La Roche-Posay My UV Patch during the China Beauty Expo in Shanghai. [Photo provided to China Daily]

Wearable devices have just ventured into a new area: beauty.

French cosmetics giant L'Oreal recently released the La Roche-Posay My UV Patch, a wearable device that combines sun protection with digital technology, at the 21st edition of the China Beauty Expo in Shanghai.

Called an "internet on paper" invention, the device comprises a heart-shaped paper skin sensor with UV-sensitive dyes that change color depending on UV exposure.

The sensor can be scanned using a compatible smartphone app that has been developed based on data collected from 400,000 users in real time and real-life conditions.

The app then advises the wearer on sun-safe behavior according to his or her skin condition.

The patch, which is thinner than human hair, is stretchable and water proof. It can last for three to five days.

"We have to look to the future ... breaking through the digital age on a worldwide scale," says Sanford Marshall Browne, vice-president of research and innovation at L'Oreal China.

"It's about personalization, so people will be able to get what is customized for them. This is the essence of a connected beauty device," he adds.

For now, the product will be offered free for educational and informational purposes, complementing La Roche-Posay's sunscreen product.

Speaking of its target audience, L'Oreal China's vice-president Chen Min says that the estimated average age of customers of La Roche-Posay is 27, and a majority of their consumption takes place on e-commerce sites, which means the brand has to pay more attention to social media to promote its beauty concepts.

The product is part of the company's endeavor in beauty electronics and sensors.

The company has a technology incubator that works with local and international startups to develop new technology.

Last year, it released Makeup Genius, a virtual makeup app, venturing into augmented reality and personalization technology. The app has been downloaded millions of times.

Research into 3-D bioprinting is also underway.

Meanwhile, Sun Qiuning, chief physician and director of the Dermatologist and Cosmetology Center of Peking Union Medical College Hospital says that as overexposure to sunlight can cause skin aging and wrinkles, sunscreen is the most practical and convenient way to stay sun-safe compared with other devices.

"From the medical point of view, the UV patch is a precise reminder of when and how much sunscreen you should apply," says Sun.

Sun protection, along with moisturizing and cleansing, are the most important steps to maintain good skin, she says.