We have wearable activity trackers that hide in wristbands, necklaces or bracelets, and ways to track our food intake and weight management through apps on our smartphones. But are you ready for your belt to start watching you? The Welt is a wellness belt (see what they did there?) that not only tracks how active you are during the day, but will also keep an eye on your waist circumference and eating habits. It connects to its companion app through Bluetooth, and a single charge is said to last for 30 days. weltcorp.com