It is four in the afternoon, you are nowhere near a charger, and your phone has just warned you it is down to 20 percent. So you dim the screen, close every app and hope. This WhatsOnTech guide shows how to make your phone battery last longer in two ways: stretching each charge today, and keeping the battery itself healthy for years, without the myths.
Find out what is actually draining it
Before you change anything, let the phone tell you where the power goes. On iPhone, open Settings and tap Battery to see which apps used the most power today and over recent days. On Android, look under Battery in Settings for battery usage; the wording varies by maker.
Look for surprises: an app you barely opened near the top, or heavy background activity (power used while you were in another app). WhatsOnTech’s rule of thumb: update, restrict or remove the top one or two culprits first, then move on to settings.
Settings that make your phone battery last longer
The screen is usually the biggest drain in daily use, so start there.
- Turn on auto-brightness. It dims the screen indoors and brightens it outside, which usually beats a fixed high setting. Brightness and fast refresh rates both cost battery, as our guide to what nits and refresh rate mean explains.
- Shorten the screen timeout. A 30-second or one-minute timeout saves power every time you put the phone down. Look in Display settings; on iPhone it is called Auto-Lock.
- Try dark mode, with modest hopes. On OLED screens, which light each pixel separately, black pixels are switched off, so a dark theme can save some power. On LCD screens it makes little difference.
- Rein in background activity. On iPhone, turn off Background App Refresh (in General settings) for apps that do not need it. On Android, you can usually restrict background battery use in each app’s settings.
- Tighten location permissions. Allow location only while an app is in use. Constant tracking costs battery, and some apps want it partly because location data helps free apps make money.
- Switch off extras you are not using. A personal hotspot left on and an always-on display keep drawing power even when you are not looking at the phone.
Low power and battery saver modes
When the battery runs low, one switch does several of these jobs at once. On iPhone, Low Power Mode dims the screen and pauses background tasks such as email fetch; most Android phones call it Battery Saver or Power saving. The trade-off is that emails and photo backups arrive later.
Why a weak signal drains the battery
With poor coverage, your phone works harder to stay connected and keeps hunting for a better signal. That is why a day in a basement can drain the battery even when you barely touch the phone. Use Wi-Fi where you can, or flight mode when you need neither calls nor data.
Battery myths you can stop worrying about
Plenty of advice on how to make your phone battery last longer was true for older phones, or never true at all:
- “Close all your apps to save power.” Apps in the app switcher are mostly paused, and reopening one from scratch can take more power than resuming it. Close an app when it misbehaves, not as a daily ritual.
- “Drain it to zero before charging.” Modern lithium-ion batteries are happy with partial top-ups, and you do not need to run the phone flat to teach it its capacity.
- “Charging overnight ruins the battery.” Phones stop charging when full. Hours at 100 percent do add a little wear, especially when warm, which is what smart charging features are for.
How to keep your battery healthy for years
Every battery slowly loses capacity as it ages. You cannot stop that, but you can slow it, mainly by avoiding heat. Apple warns that surrounding temperatures above 35 degrees Celsius can permanently reduce battery capacity, and the same basic chemistry sits in almost every phone.
The WhatsOnTech habit: keep the phone off sunny dashboards and windowsills, and avoid charging it under a pillow, while gaming hard or on a cheap unbranded charger. A battery that is full and hot ages faster, so never leave it charging in a warm car, and remove the case if it heats up on the charger.
Let the phone manage its own charging
Many modern phones can learn your routine and hold the charge at around 80 percent overnight, finishing just before you usually unplug. On iPhone this is Optimised Battery Charging, and newer models add a charge limit. Most big Android makers offer something similar under Battery in Settings, such as adaptive charging or Battery protection on Samsung Galaxy phones, which can also stop charging at a level you choose.
Check battery health and decide on a replacement
If your phone now dies well before bedtime despite all this, the battery may be worn. On iPhone, open Settings, tap Battery, then Battery Health (the label varies by model) to see its maximum capacity compared with a new battery. Some Android phones show similar details under Battery or About phone, or in the maker’s support app.
A new battery is often the cheapest way to keep a phone you like. WhatsOnTech’s advice is that it makes sense when:
- The phone still gets security updates. Check how long it will be supported, the same test we use for how to choose a smartphone.
- Everything else still suits you. Only the battery lets you down.
- You use the maker or an authorised repairer. Cheap unbranded batteries can be poor quality, or even unsafe.
If updates end soon or the phone struggles in other ways, a new phone is usually the better deal. Either way, back up your phone before it leaves your hands.
The takeaway
To make your phone battery last longer, look before you tweak: the battery screen shows what is draining it, a handful of settings do most of the work, and the app-closing and drain-to-zero rituals can go. For the long run, keep the phone cool and let it manage its own charging. Small habits that quietly save you hassle are the ones WhatsOnTech enjoys sharing most, and there are more in our phones and gadgets guides.