Mobile Phones iPhone & iOS What You Need to Do If You See a Red iPhone Battery Icon Know when it's time to recharge By Sam Costello Writer Sam Costello has been writing about tech since 2000. His writing has appeared in publications such as CNN.com, PC World, InfoWord, and many others. our editorial process Facebook Twitter Sam Costello Updated November 12, 2019 iPhone & iOS Switching from Android Tweet Share Email Your iPhone screen shows you all kinds of useful information: the date and time, notifications, playback controls when you're listening to music. In some cases, the iPhone screen just shows icons like different-colored batteries or a thermometer. Each icon gives you useful information — if you know what it means. It's important to understand what these icons mean and what you should do when you see them. In at least one case, it can save your iPhone from serious damage. The battery icons discussed in this article can appear both in the top right corner of the screen and, in some cases, on the lock screen of the phone. Wherever you see the icon, the colors all mean the same thing. Red Battery Icon on iPhone: Time to Recharge You'll encounter a red battery icon on your iPhone if it's been a while since you last charged your iPhone. When you see this, your iPhone is telling you that its battery is low and needs to be recharged. The charging cable icon beneath the red battery icon that's shown on the lock screen is another hint that you need to plug in your iPhone. Your iPhone still works while it shows the red battery icon, but it's hard to know how much life it has left (unless you're viewing your battery life as a percentage, that is. We recommend it). It's best to not push your luck. Recharge your phone as soon as you can. If you're not able to charge it right away, you should try Low Power Mode to squeeze more life out of your battery. More on that in the next section. If you're always on the go and can't charge your phone regularly, it might be worth buying a portable USB battery or a battery case to make sure you don't run out of juice. Orange Battery Icon on iPhone: Low-Power Mode You won't see this icon on the lock screen, but sometimes the battery icon in the top corner of the iPhone's home screen turns orange. This color signals that your phone is running in Low Power Mode. Low Power Mode is a feature of iOS 9 and up that stretches your battery life for an extra few hours (Apple says it adds up to three hours of use). It temporarily turns off unnecessary features and tweaks settings to squeeze as much life as possible out of your battery. Green Battery Icon: iPhone — Charging Seeing a green battery icon on your lock screen or in the top corner of the screen is good news. It means your iPhone's battery is charging. If you see that icon with a little lightning bolt next to it, you know your iPhone is plugged in. Still, it's good to know to look for it in case you're trying to charge and something isn't working properly. In some more recent versions of the iOS, the battery icon is white, rather than black or any of the other colors mentioned here. A white icon means that everything is working fine. Red Thermometer Icon: iPhone Is Too Hot Seeing a red thermometer icon on your lock screen is uncommon — and it's serious. The red thermometer can be a little scary since your iPhone won't work while the thermometer is present. An onscreen message tells you that the phone is too hot and that it needs to cool down before you can use it. This is a serious warning. It means that your phone's internal temperature has risen so high that the hardware could be damaged (in fact, overheating has been linked to cases of iPhones exploding). When the device overheats, the iPhone protects itself, according to Apple, by turning off features that could cause problems — including automatically stopping charging, dimming or turning off the screen, reducing the strength of the connection to phone company networks, and disabling the camera flash. If you see the thermometer icon, immediately get your iPhone into a cooler environment. Then shut it off and wait until it's cooled down before you try restarting it. If you've tried these steps and let the phone cool for a long time but are still seeing the thermometer warning, you should contact Apple for support.