I built an iPhone/iPod Touch app and companion app for the Pebble Watch (and Apple Watch coming soon) that works with a Google Cardboard headset to digitally enhance the sight of people who are visually impaired. My father is nearly blind and we were looking at a similar product by eSight, but they charge $15,000 USD for their headset. Frustrated by the ridiculous cost, I build my own using an iPod touch, Pebble Watch, and a headset, the total cost of which was about $400. The custom software will allow him to adjust brightness, contrast, saturation, and zoom from the iPhone/iPods camera using the watch as a control. These features can greatly improve what a person with severe visually disabilities are able to see and fraction of the cost.

More info here.