Air pollution is a big health hazard around the world, causing as many as 7 million premature deaths annually, according to the World Health Organization. That's why a wearable personal pollution monitor, which tracks the amount of dangerous chemicals in the air and provides warnings via your smartphone when you need to seek refuge indoors, is a tool that could make a major difference for people who live in big, polluted cities, particularly asthmatics.
TZOA, for example, is a button-sized sensor that can be attached to your clothing or a purse, to continually monitor and gather data on air quality, temperature, humidity, atmospheric pressure and even solar UV exposure. It streams that data to a smartphone app, which not only gives you continuous reports, but also contributes to a crowd-sourced effort to map pollution hotspots in cities. TZOA's manufacturer plans to market the product by late 2015. Companies are developing at least two other gadgets with similar functions —AirBeam and Clarity [sources: Alba, Handwerk, Rodin].