After the cool factor wears off with health and wellness wearables, ease of use and unobtrusiveness matter more when people move to the next thing and get on with their lives. In order to convince most people to continue to use wearables and to attract new waves of users, technology developers need to embrace passive designs.

Contact-free sensors using radio or light waves may be the ultimate passive wearable tech, but they only work when the user is in range. Clip-and-forget devices that attach to clothing present another passive possibility, but they need to be rugged enough to withstand frequent harsh handling, run for relatively long periods without battery replacements or recharging. And regardless of the physical format, any gathered sensor data must be accurate.

The original Spire Stone that launched in 2014 was a brooch-like clip-on device with one-week battery life and a $150 price tag. The first model tracked respiration and motion, sending data via Bluetooth low energy to an iOS device and app from which the data was sent to the cloud.

Spire recently launched Health Tags, small devices about the size of a laundry tag that users adhere to clothing. Spire charges $50 for a single Health Tag, but encourages customers to buy them in bulk; 3-packs cost $129 and an 8-pack sells for $299 (currently on sale for $199). Buy Tags by the box and put them on clothing you usually wear, such as bras, gym shorts, and sweaters. Spires claims the Health Tag’s battery lasts for up to a year and a half and that the device is clothes washer and dryer proof. If you join the company’s extra-cost Spire+ program, they will replace any tags for free when their batteries run out.  When the  The Tag tracks heart rate, respiration rate, activity, calories, and sleep. Depending on the data transmitted to an associated iOS mobile device, a health coach app displays suggestions for healthy behaviors such as exercising or sleeping more.

The new Spire tech has more functions, much longer battery life, and a significantly lower price than the first design. The iOS limitation leaves Android users out, but the company claims that they will provide an Android version “in the near future.” The Health Tag’s stick-and-forget attachment method is a logical step forward to help consumers benefit from health and wellness tech over time.