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The Belty motorized belt keeps you comfortable, tries to keep you active

Fitness and activity trackers come in many shapes and sizes. Some you wear on your wrist; others you stick in your ears; and some you clip onto your belt. Emotia's prototype activity tracker actually is a belt; or more specifically, a belt buckle called Belty. As you'd expect, it measures steps like every other tracker, and connects to your phone via Bluetooth to feed this data into an app, which acts as a virtual fitness coach. You can also set it to vibrate when you've been sedentary for too long and, more importantly, it can keep tabs on your changing waist measurement, which can be a good indicator of your risk of developing weight-related conditions. What I've described so far is all well and good, but forget that, because this belt buckle is also motorized, and capable of tightening and loosening itself to keep you as comfortable as possible at all times.

After listening to a lengthy disclaimer from an Emotia rep, explaining this is very much an in-development product (and not to judge it too harshly because of that fact), I removed my belt and replaced it with Belty. Having adjusted it appropriately, I was instructed to double-tap the buckle to lock in the tightness setting, and because I didn't have any food to expand my stomach with, I did the next best thing: I sat down. As soon as the pressure on the buckle increased, as it naturally does when you compress into a chair, the motor kicked in and loosened it until the belt reached the same tightness level as it had been when I was standing up. Rising again, the whirring began, and it tightened itself up once more. The movement is slight, but it's easy to feel this "smart belt" at work, and I was suitably impressed, not to mention comfortable (and still wearing pants).

Belty is still at the early prototype stage, and needs significant shrinking before it can become a commercial product, but Emotia's confident it can build an inconspicuous and desirable buckle by the end of 2015. Eat your heart out McFly.