Warby Parker, the online glasses retailer, has a try-on function that lets consumers upload a picture of themselves to see what various frames look like on their faces. A competitor, glasses.com, which was recently purchased by the eyewear giant Luxottica, has an app that creates a 3-D model of shoppers’ faces for virtual try-ons and lets them adjust the glasses on their faces by touching the screen. Cisco and others have developed virtual dressing room technology, though it has not been widely adopted.

There is also a growing genre of makeup (or makeover) apps, including Perfect 365, FaceTune and Visage Lab, that make it possible for people to touch up their photos, eliminating a pimple here, a wrinkle there, putting a flush in cheeks, even shaving off a pound or two — the better for posting on Instagram and elsewhere.

But the new L’Oréal app deals strictly in reality — how its products look on a potential customer’s untouched face — for better or worse. It also offers a chance to virtually try 16 “curated looks,” like “smoky eyes” devised by the celebrity makeup artist Billy B.

To accomplish the virtual mirror effect, the L’Oréal app had to be intuitive enough to discern between, say, the skin of lips, cheeks and other facial features. Developers said they tested lip, eye and cheek products on hundreds of people of numerous ethnicities in 400 different lighting conditions and conducted extensive studies, including how a product dries on the skin. The company would not say how much money it invested in the effort.

“While we provided the facial mapping technology, working with L’Oréal to ensure what consumers ultimately see in the app — in terms of color, texture, opacity, shine and overall look — that was tremendous,” said Ron Ryder, the chief executive of Image Metrics.

The app is the first major project to come out of a high-tech incubator that the beauty company opened a year and a half ago in a suburban office building in Clark, N.J., about 30 minutes outside New York City. There, a team of Ph.D.s, physicists, computer scientists and others is working to help the company develop a high-tech relationship with the consumer in a field that doesn’t naturally lend itself to connectivity.

“The reason why we started it is we see the beauty consumer has changed in terms of what they actually want in a product and an experience,” said Guive Balooch, global director of the company’s Connected Beauty Incubator, who has a Ph.D. in biomedical engineering and came to L’Oréal from the pharmaceutical field. “We are moving more and more toward service, personalization, toward customization.”

Though L’Oréal plans to unveil the Makeup Genius app this week in New York and Cannes, France, during the annual Cannes Film Festival, it won’t be available to consumers until June, and this first phase will not be available on Android devices. Products won’t be for sale on the app itself — at least not yet.