Mevics - Wearable that monitors posture & physical activities.
SitApp - Desktop app to monitor posture and remind you to sit up!
Darma - Quantified-self for your ass and posture (pre-order)
BLiiNK - An AI-powered application that helps to improve your eye health, correct your sitting posture, and boost your productivity while working at a computer without recording or storing any visuals.
PoseAlert - Keep correct posture while sitting
Curie - Your personal posture trainer at work