We have some bad news about your smartphone: it's gross.

"Cell phones are one of the dirtiest things we encounter daily," Charles Gerba, PhD, a microbiologist and professor at the University of Arizona who is often referred to by his nickname, Dr. Germ, tells Health. Need proof? In 2017, researchers from his university studied germs on the cell phones of high school students and found that their devices carried 10 times more bacteria than most toilet seats. Yikes.

You spend all day with your phone, setting it down on tables, chairs, public benches, bathroom counters, and even more unsightly places. Then there's the more visible grime that gets on or in your phone from dropping it in the dog park, leaving it in your sweaty jean pockets, or letting your child pour Cheerio dust all over it.

You probably don’t clean your smartphone as much as you should. Whether you’re concerned about coronavirus or just common flu and cold germs, regularly disinfecting your smartphone will help lower your overall risk of getting ill. Here’s how to do it.

Smartphone manufacturers have instructions to help you safely clean your smartphone. These generally involve wiping it down with a damp lint-free cloth and avoiding harsh chemicals, abrasive cleaners, and pressurised air.

Harsh cleaning products can accelerate the rate of wear on the oleophobic (oil repelling) coating on your screen. This coating will gradually degrade as you use your device over several years. Using alcohol and household sprays may speed up the process. Using bleach and other harsh chemical cleaners will strip it away completely.

What NOT to use when cleaning your phone

Alcohol wipes might seem like an easy way to clean grime off a phone, but fight this instinct with every phone-loving fiber of your being. Bleach, vinegar, alcohol, and most harsh disinfectant chemicals can clean the sides and back of an Android phone or iPhone, but those chemicals need to stay far away from the glass front of your phone (and glass back if you have one), as they will eat away at the oleophobic coating that your phone uses to help fight fingerprint smudges.

What if my oleophobic coating is already gone? Or I don't care about it? The oleophobic coating wears down naturally over time, so if yours is already gone, then feel free to go to town with some alcohol wipes, just be careful as you do. Make sure you don't let the liquid from the wipe seep into any ports or pinhole mics, and make sure you let the solution dry completely from the phone before you re-apply your case. These chemicals don't play nice with the interior components of your phone, and if they seep in far enough to trip the water damage sensor most phones have these days, you might not be covered for a warranty replacement if something shorts out.

Compressed air can be useful since it blows dust out of hard-to-reach places. However, you need to be very, very careful when using it with a phone as compressed air can damage pinhole mics and other components quite easily with their precise, pressurised air blasts.

How to disinfect your phone by hand

1. Turn your phone off and take it out of it's case.
2. Add a small amount of gentle cleaning agent and a drop or two of antiseptic to a small container, and mix this with some warm water.
3. If the case made of safe-to-wash materials like TPU/silicone and hard plastic, give the case a good clean in the warm soapy water and let it air dry. 
4. Submerge a wash cloth in the cleaning solution, ring out excess water in the cloth so that it's damp.
5. Thoroughly clean the outside of your device. Be careful not to allow water into any ports or crevices on your device.
6. Dry your device with a dry cloth and allow the device to air dry while switched off for at least 10 minutes.
7. If you have any other tablets or laptops, consider cleaning these with your cleaning solution.
8. Before turning your device on, ensure or ports and crevices are perfectly dry.
9. Re-apply your case and turn your device on.
10. Once you’ve cleaned your smartphone, wash your hands thoroughly for at least 20 seconds, as per the CDC recommendations.

Disinfect Your Smartphone Regularly

If you touch your phone after touching an unclean surface, bacteria and other microbes will be transferred onto it. Even if you go home and wash your hands thoroughly, by the time you’ve touched your phone, those microbes have been transferred again.

This doesn’t mean you should obsessively clean your phone multiple times a day, but it’s a good idea to do so when you get home from being out in public.

You could take all the precautions in the world and still get sick. All you can really do is help limit your exposure by taking a few basic precautions: Wash your hands regularly, don’t touch your face, and disinfect personal effects that may harbour bacteria and other microbes.