It’s about to get cold in much of the Northern Hemisphere. Soon we’ll clutch mugs of hot chocolate for warmth, don so many layers that we look more like marshmallows draped in wool and polyester than human beings, and lament how little we appreciated the sun’s warm embrace during the summer months. Now we’ll also have something else to worry about: our smartphones.

Phones weren’t made to withstand extreme temperatures. Neither are people, but when we get cold we can put on a jacket, shiver a little bit, or huddle up. Smartphones can’t do any of those things. This begs the question: How cold, exactly, does it have to get before our phones will start to malfunction?

There is no clear-cut answer. Different manufacturers use different components in their phones, which means there are slight variations in how each responds to the cold. Generally, though, their displays start to flicker, they have problems connecting to wireless networks, and eventually their batteries will stop working, whereupon they become very expensive icicles.

Popular Mechanics tested a variety of smartphones in 2009 to find out when they would go through those stages of (temporary) death, taking them into an environmentally controlled room and dropping the temperature until the phones experienced problems. The phones were then brought back to room temperature to see if any damage was permanent.

But those tests were on dumb phones. So PCWorld ran a similar experiment in 2012 on a number of smartphones and dumb phones. The smartphones fared worse: The iPhone 4S was actually the first to experience problems, at 23 degrees Fahrenheit, while some of the “feature phones” didn’t have any malfunctions until they reached -13 degrees.

That jibes with Apple’s recommendation for iOS devices not to drop below 32 degrees Fahrenheit. After that, the company warns, they’ll likely encounter battery issues and other problems. So chances are good that your iPhone’s battery isn’t going to be as long-lived once the temperature drops below freezing.

Other smartphones have other breaking points. PCWorld said most of the smartphones it tested encountered issues between around 5 and -4 degrees Fahrenheit. Samsung’s fared the best — unsurprising, as its devices have had the opposite problem recently — when the Galaxy S II ran until -22 degrees Fahrenheit.

Basically, if you’re cold, your phone will be, too. You can’t layer your smartphone, but you can keep it in your pocket or try not to use it outside. Don’t worry if something bad happens, though: Both Popular Mechanics and PCWorld found that the cold didn’t cause permanent damage.

That’s one winter mystery solved. Now if only we could figure out proper sidewalk etiquette these cold days would become far more bearable.

Photos via Popular Mechanics, Getty Images / Roberto Serra