LAS VEGAS—More than 100 million Americans suffer from chronic pain, and now there’s finally a consumer-grade wearable that’s designed to provide some relief. Announced at CES 2015, and available this spring for about $250, Quell is a wearable that takes time-tested TENS technology to the consumer market.
TENS stands for Transcutaneous Electrical Nerve Stimulation, a technology that applies a small electrical current to the surface of your skin—in the case of Quell, the electrical leads make contact with your calf, which Quell describes as a “veritable USB port” for plugging into your body’s nervous system.


Small electrical impulses course from your calf to your lower brain, which in turn releases the body’s natural opiates to aid in pain relief. TENS technology is proven, but doesn’t work for everyone, so Quell will be offering a 60-day money-back guarantee—a nice safety net for skeptics. When you wear a TENS device, you feel only a faint buzzing, tingling sensation where the leads make contact with your skin. Pain relief usually kicks in within 15 minutes (assuming it comes at all).
The Quell sensor promises 40 hours of pain relief on a single charge, and is designed to be worn 24-7. It even reduces to 80 percent intensity during the middle of the night to ensure a good night’s sleep. Quell also includes an accelerometer that provides sleep data through an iOS app.

Why this matters: Quell is one of the very few health-and-fitness wearables I’ve seen to receive FDA approval for the over-the-counter consumer market. It costs a lot of time and money to win the FDA’s blessing, so clearly the Quell manufacturer thinks it has a winner. It’s worth noting that Quell says its device is double the strength of existing TENS devices, and that it has the unique ability to calibrate itself for optimal stimulation levels—and thus better pain relief. It’s also much more convenient to apply than existing TENS gadgets, which tend to look like science experiments.