Phone Myths and Facts: 12 Battery, Charging and Care Tips Most People Get Wrong

Myth: you should close all your apps to save battery

False. Apple says closing all your apps does not affect your device's overall performance, and that you should only close an app when it is unresponsive. Apps you are not using only use power when they are doing specific background tasks.

Myth: drain the battery to 0% before charging

False for lithium-ion. Apple says there is no need to let the battery discharge fully, and Google says you do not need to run a Pixel from full to empty to teach it its capacity. Battery University says partial discharges are less stressful than full ones. Letting a phone go flat often is harder on it, not easier.

Myth: a new phone needs a long first charge

False. Apple and Google say lithium-ion batteries do not need full charges or full discharges to learn their capacity, and neither company asks for a long first charge. Charge a new phone when you want and use it straight away.

Myth: charging overnight will ruin the battery

Mostly false. Phones stop charging when full, and iPhone, Samsung and Pixel all have overnight modes that hold the charge at about 80% until shortly before you wake. The real risks are heat and safety: Apple says not to charge under a pillow or blanket or sleep on a charging device.

• Best way to charge your phone

Myth: fast charging destroys batteries

Exaggerated. The phone controls fast charging and slows down after about 80%, as Apple describes. Battery University says ultra-fast charging adds stress, mainly in the later part of the charge and in bad temperatures. The useful version of this tip: do not fast charge a phone that is already hot.

Myth: any charger is fine if it fits

False, and this one matters for safety. Apple says adapters that do not meet safety standards could pose a risk of death or injury. Google says other adapters can damage a Pixel or its battery. Samsung lists non-genuine chargers as a cause of overheating. A branded charger that meets the standards is fine; it does not have to be the phone maker's own.

• Chargers and accessories on Mobile Market

Myth: put a wet phone in rice

False. Apple says putting an iPhone in a bag of rice could let small rice particles damage it. Apple and Samsung both say to air dry the phone in a dry place with airflow, with no heat, and not to charge it until it is dry.

• Phone dropped in water: what to do

Myth: water resistant means waterproof

False. Apple says water resistance is not permanent and decreases with normal wear, and that liquid damage is not covered under warranty. An IP68 phone can survive a drop in the sink. It is not meant for the swimming pool or the shower.

Partly true: Airplane mode saves battery and helps charging

It does save battery in the right place. Apple says that in poor coverage the phone keeps searching for a signal, which drains the battery, and suggests Airplane mode there. With the radios off, less power is being used while the phone charges, so charging can finish a bit sooner. We did not find any official figure for how much faster, so do not expect a miracle, and remember you cannot take calls in Airplane mode.

True: a nearly full phone can slow down

Google's Android Help says a phone can start having issues when less than 10% of storage is free. On iPhone, Settings > General > iPhone Storage shows what is using space and offers recommendations, including offloading apps you do not use while keeping their data. Delete old videos and downloads before you blame the phone.

True: heat damages batteries more than anything else

Apple says ambient temperatures above 35°C can permanently damage battery capacity. Battery University says the worst situation for a lithium-ion battery is being kept fully charged at high temperature. A phone on a car dashboard in July, at 100% and charging, is the worst case.

• Why is my phone heating up?

True: battery health apps cannot fix your battery

No app can increase battery capacity. Apple describes battery ageing as chemical. Android apps that show battery health only estimate it, and booster or cleaner apps that promise to restore it cannot change chemistry. Use the brand's own tools: Battery Health on iPhone, Samsung Members diagnostics, or Battery health on Pixel 8a and later.

• How to check battery health

Buying or selling a phone?

Many of these myths come up when people price a used phone. A seller who swears the battery is like new because it was always charged to 100% overnight is not lying, but the screen in Settings tells you more than the story does.

• Browse phones and accessories
• Sell your phone on Mobile Market
• Battery health on used phones

Does Airplane mode make a phone charge faster?

It can help a little because the radios are off and use less power, but no phone maker publishes a figure for how much. Apple recommends Airplane mode mainly where signal is weak, because searching for signal drains the battery.

Does full storage slow down a phone?

It can. Google's Android Help says a phone can start having issues when less than 10% of storage is free. Free up space by deleting large videos, downloads and unused apps.

Is it bad to let your phone die completely?

It is not helpful. Lithium-ion batteries do not need full discharges, and Battery University says smaller discharges are less stressful. Apple also says storing a fully discharged battery can push it into a deep discharge state where it cannot hold a charge.

Do I have to use the original charger that came with my phone?

Not necessarily. Apple says third-party adapters that meet safety standards are fine for iPhone. Google recommends the Pixel's own adapter because others can charge slowly or damage the battery. Avoid unbranded chargers either way.