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From overnight charging fears to the dangers of fast charging and wireless pads, iPhone charging myths are everywhere. Let’s separate the truth from the tech lore, so you can charge smarter without stressing over your battery’s health.
1
Using Your iPhone While It’s Charging Is Bad
Apart from being a good reason your mom would tell you to get off your phone, this myth doesn’t hold any water. At least not anymore—any iPhone (or smartphone, for that matter) made in the last decade or so should be fine if you use it while it’s plugged in.
Doing that will slow down charging marginally since some of the power will go into what you’re using it for, but by a negligible amount.
What you should watch out for, though, is the heat. Sometimes, your iPhone could get pretty toasty while charging, and the heat might be enough to discomfort you. Heat is also bad for your phone. Using your phone while charging might contribute to that—generally not enough to be a problem, though, since any modern Apple device has a thermal management system to prevent overheating.
2
You Shouldn’t Leave Your iPhone Plugged In Overnight
The lithium-ion battery in your iPhone has a limited lifespan, and overcharging and undercharging stress the battery, causing it to wear out faster. That’s why this myth exists—it was true once. Now, iPhones have advanced smart charging technologies that prevent overcharging.
When your iPhone reaches 100 percent, it stops charging and only draws enough power to keep it fully charged. Also, any iPhone running iOS 13 (iPhone 6S) or later has Optimized Battery Charging set up by default.
This feature learns from your schedule and delays charging beyond 80 percent, so your phone spends less time at 100 percent. iPhone 15 and later takes it a step further, letting you set a charge limit under 100 percent. This way, your phone never even reaches 100 percent.
3
It’s OK to Let Your iPhone Charge on Your Bed
Now we’ve established that it’s fine to charge your iPhone overnight, I have to add that it’s definitely not OK to let it charge on your bed. Apart from the minor fire hazard (especially when using faulty cables and chargers), the compounding heat from a mattress will degrade your battery faster.
Although it may not look like it, iPhones need airflow to cool properly. Even with Apple’s advanced thermal regulation system, heat will likely build up if the phone cannot cool. If you need your phone near you while sleeping, put it on a bedside table instead of smothering it on a mattress, pillow, or underneath your body.
4
Fast Charging Has Negative Effects on Your Battery
Theoretically, yes, fast charging causes more heat, but the negative effects are so inconsequential that they pale compared to the benefits of fast charging. However, you should feel free to go ahead and fast charge any iPhone from the iPhone 8 or later. They can handle it.
Apple has conducted rigorous testing (explained on Apple’s website) to ensure that fast charging is completely safe. The company has even added guardrails to protect the phones in extreme temperatures. However, different iPhones can handle different watts depending on the generation.
In a previous post, we explained everything you need to know to fast-charge your iPhone—check it out before fast charging.
5
Charging Your iPhone In Low Power Mode Will Ruin the Battery
I haven’t seen this one as much on the internet, but I’ve heard it from friends and family. I live in a tropical climate, and the heat and humidity affect batteries in ways that might trigger erroneous beliefs. Perhaps this myth came about because batteries tend to fail more in my side of the country.
Regardless, it’s unfounded; low power mode has little to no effect on charging, as we’ve proven in tests. Of course, it also has no adverse effects on your battery either. In fact, Low Power Mode might help improve battery lifespan since it forces the iPhone to draw less power.
6
A Non-Apple Charger or Power Bank Is a Disaster Waiting to Happen
False. There are many MFi (Made for iPhone) certified trusted retailers, like Anker, Spigen, Mophie, Belkin, and UGREEN. Using any of these on your iPhone should be perfectly fine. You don’t need to worry about anything happening to your phone or the brick melting the outlet it’s plugged into.
For further proof, Apple recommends using verified third-party chargers and power banks, which it sells in the online Apple Store. You should avoid cheap knock-offs and substandard chargers.
7
Any Off-Brand Charger Is Fine as Long as It Works
The fact that a cheap charger you found randomly on Amazon or at a street vendor works doesn’t mean it’s good for your phone.
Not only are poorly built chargers harmful to your battery, but they could also pose physical safety risks due to short-circuiting and fires. Some could even damage your iPhone’s charging port (which happens far more often than people think).
Lastly, you can expose yourself to data risks because some bad actors sneak malware into your phone by hiding it inside the cable heads. Thankfully, there are ways to check if your smartphone charger is safe to use.
8
Powering Off Your iPhone Makes Charging Faster
The idea behind the myth is probably because your iPhone uses less power when it’s off. However, charging speed depends on so many other factors that powering off your phone is essentially pointless.
According to my tests with an iPhone 14 Pro, my phone charges much slower while powered off, likely because it can no longer communicate with the fast charger through the iPhone’s USB Power Delivery (PD) protocol.
That’s one reason iPhones are programmed to power on when you plug them in.
9
Wireless Charging Is Worse for Your Battery
Not necessarily. It’s true that wireless charging generates more heat and charges your phone longer. The heat could be bad for your battery, but any standard wireless charger will dissipate the heat properly—this, combined with Apple’s superior MagSafe connection and thermal regulation, should make wireless charging safe for your battery.
Just make sure you charge your phone in a well-ventilated room and place it on a surface that doesn’t trap heat.
10
You Should Let the Battery Drain Completely Before Charging
This is one of the worst things you could do for your battery’s lifespan. iPhone batteries typically have around 500 cycles worth of lifespan. This means they can charge from 0 to 100 percent 500 times before the battery reaches the end of its life. If you keep letting it die before charging it, you will run through those cycles quickly.
I recommend keeping your phone between 40 and 80 percent charged and charging it multiple times throughout the day. It’s not convenient, I know, but it’s the price you’ll have to pay to keep your battery healthy for longer.