Afraid there may be peanuts or other allergens hiding in that cookie? Thanks to a cradle and app that turn your smartphone into a handheld biosensor, you may soon be able to run on-the-spot tests for food safety, environmental toxins, medical diagnostics and more.

The handheld biosensor was developed by researchers at the University of Illinois, Urbana-Champaign. A series of lenses and filters in the cradle mirror those found in larger, more expensive laboratory devices. Together, the cradle and app transform a smartphone into a tool that can detect toxins and bacteria, spot water contamination and identify allergens in food.

Kenny Long, a graduate researcher at the university, says the team was able to make the smartphone even smarter with modifications to the cellphone camera.