The latest device comes from skin-care brand H2o+, and — as you might have guessed from the company's name — it's all about detecting your skin's hydration levels in order to lead you to the right moisturizer. If the science sounds familiar, that's because it is: The MiLi Skin Moisture Meter is similar to a machine you can find at Sephora's New York City flagship store , but the difference is that this tool is palm-sized — like a little USB drive, only cuter and with way more beauty benefits.