It's not news that, but there's a difference between knowing that about your device and seeing the germs up close in all their furry, florid glory.
Molecular biology undergraduates at the U.K.'s University of Surrey recently got a stark view of just how much bacteria crawls on their phones when instructor Simon Park had them imprint their devices onto petri dishes filled with a bacteriological growth medium and wait a few days to see what bloomed.
Spoiler alert: The experiment turned up lots of bugs, though Park says most of the bacteria were harmless varieties normally found on the skin. Disease-carrying bacteria such as Staphylococcus aureus were also found, however.
"The ecological niche on the body for Staphylococcus aureus is the nostrils, so a furtive pick of the nose, and quick text after, and you end up with this pathogen on your smartphone," Park told Wired.co.uk.
Park -- who dabbles in all sorts of microphotography of natural phenomena -- describes himself as a "poet scientist who works with living matter in order to explore the inherent creativity of the natural world and to reveal its subtle, and usually hidden, narratives."
Indeed, it's as if each bacteria-covered cell phone tells its own story. Click through the gallery below to see what tales they have to tell.