that recommend shoppers products like foundation or eye shadow specifically for their unique skin type. there are plenty of personalisation services out there, but what about a device designed to detect the skin's undertone? skin undertone in cosmetics is basically what we call hue in science. it's not about "is your skin light or is it dark?", so it's nothing to do with lightness. it's to do with the colour that runs through your skin. so, you can be very light and be pink, you can be very light and be yellow. and it's very important to know that, so you can actually get beauty products that work for you. there are different ways to measure skin undertone, but farah believes her company's skin—colour chart, which powers the tool, makes the method unique. having an actually olive complexion, i really struggled to find make—up that would match. and being a biochemist,