A gadget that perfects your posture

The LUMOback may prevent or reduce back pain by teaching you the proper way to sit and stand. It uses a sensor attached to a belt that fits around your lower back. After you calibrate the device to your body geometry, it determines how your spine and pelvis should align while you sit and stand. If you slouch, gentle vibrations remind you to straighten up. It also connects wirelessly to an iPhone or iPad app, which tracks how much time you spend sitting, standing, walking, and lying down. LUMOback costs about $150 and is available online.