Chronic bad posture – whether you're slumping in a chair or slouching in line – can lead to back pain. But reminding yourself to sit yoga-straight is not always easy. The Lumoback app and its accompanying device are built to help. Download the app for iPhone or Android devices and sync it with the strap Lumoback provides, complete with a sensor that sits on your lower back. Once synced, the strap reads your position and, if you slouch, will give you a gentle buzz to remind you to sit up and stay straight.