Delhi-based fitness freak Archit Kashyap is inseparable from Prkruti Lite. At first sight, you would assume it’s an external drive attached to his phone. It is, in fact, the world’s smallest personal air-quality tracker, weighing just 25 grams. Operated with the Prkruti Lite mobile app, the device monitors the level of pollutants in the surrounding air. Kashyap also has a Shellios Clean Air Helmet. It costs Rs 4,500 and uses an air-purifier system attached at the rear, which also has a micro USB charging port. It pulls air through a filter and circulates it in front of the face. A chin curtain stops ingression of polluted air.