TL;DRThe Lumia 2 is a pair of smart earrings that track blood flow to your head in real time, offering insight into energy, focus, and brain fog.The tech lives in a tiny earring back called the Lumia Core, which attaches to Lumia’s own jewelry or your existing earrings.Pricing starts at $249 for the device, plus $9.99/month for a membership.Smart rings may be one of the trendiest fitness tracking form factors of the moment, but one company is making the case that health tracking belongs on your ear. Lumia today announced Lumia 2, a smart earring that tracks blood flow to your head in real time. According to the company, the device offers insight into energy, focus, and mental clarity. It’s a bold pitch for what Lumia calls the “world’s first smart earrings,” but it’s also one built on clinical roots rather than consumer fashion.Lumia originally developed its sensing tech alongside researchers at Johns Hopkins, Duke, and Harvard to help patients with chronic blood-flow disorders. Now, the company wants to make that same technology more accessible by packaging it inside a jewelry-like earring back it calls the Lumia Core. The Core houses an optical sensor and other health sensors, plus a processor and battery, and attaches to a visible earring front that is interchangeable. Lumia sells modular hoop and stud options in gold, silver, and clear finishes, but a patent-pending SwitchBack mechanism also lets the Core attach to most push-back earrings you may already own. Lumia also sells a cuff version of the device for people without pierced ears. The whole package weighs less than one gram.