Because so many people have iPhones, a lot of conventional wisdom about iPhone battery life can be similar to folk wisdom – the body of knowledge and experience that comes from the beliefs and opinions of ordinary people.

Yet that is not to say there are not ways you can improve your battery life by changing specific settings, or the way you use your iPhone.

Here are five common myths about iPhone battery life, what you can do about them, and sources where you can find additional information:

Myth #1: closing apps you are not using can save battery life

It is a safe bet that at some point you know someone who compulsively shuts off apps on their smartphone to save battery power.

They hit the home button twice, and then swipe up on various apps they have used in the past until the carousel is cleared.

In fact, this does not save battery, and may actually use extra power when you reopen apps you have totally switched off.

Apple’s top software executive even confirmed this in an email to a user.

“You should force an app to close only when it is unresponsive,” Apple wrote on a support page.

Myth #2: charging your phone overnight can hurt the battery

For years, some users have insisted that plugging your smartphone in while you sleep can harm the battery.

Maybe this made sense years ago, but it is overblown today.

Instead, your battery lifespan depends on “cycle count”, or how many times you have charged it over its lifetime.

Modern smartphones, including the iPhone, have advanced power management that means that they will not take in more current than is necessary to charge them – meaning that leaving it plugged in after it reaches 100 per cent will not have any effect.

“All rechargeable batteries are consumables and have a limited lifespan – eventually their capacity and performance decline so that they need to be replaced,” Apple writes in a support document.

Myth #3: Apple’s US$29 battery replacements are guaranteed to improve your device’s battery life

There was a minor scandal last year when it was discovered that Apple sometimes reduced the power to iPhone processors with old and spent batteries.

Basically, Apple did make some iPhones appear to run slower. It fixed the issue in a software update and offered US$29 replacement batteries to users.

However, just because you can get a battery for US$29 does not mean it will solve all your battery life issues.

For some people, it could. But if you go to an Apple store and the technician said your battery seems fine, it probably is.

“I would say less than 10 per cent of the phones we have ordered batteries for actually need a battery, based on diagnostics,” a Genius at a US Apple store told Business Insider earlier this year.

To check if your battery needs a replacement, go to Settings > Battery > Battery Health (Beta).

If you do not see it, you probably need to update your iPhone software.

If your “maximum capacity” is under 80 per cent, you might want to change it.

Otherwise, if you are only missing a few percentage points, you can probably wait.

Myth #4: turning off settings such as Bluetooth and Wi-fi will always save your battery life

The standards for Bluetooth and Wi-fi say that when they are on and not in use, they use no power, so there is no need to turn them off to eke a few more minutes out of your phone.

In fact, if you have an Apple Watch and you turn Bluetooth off, it will stop not only your Apple Watch from working correctly, it could drain the battery faster, too.

However, if you are in an area with a bad mobile phone connection, that can negatively impact on your battery life.

Turning on Airplane Mode in these kinds of situations can save battery life.

In fact, Wi-fi uses much less power than a mobile network, so Apple recommends keeping Wi-fi on at all times.

Myth #5: letting the iPhone adjust brightness automatically hurts battery life

While it might be tempting to manually control your iPhone brightness, dimming it when you need extra juice and ramping it up when you do not, Apple says that its auto-brightness setting actually saves battery life.

To turn it on, go to Settings > General > Accessibility > Display Accommodations > Auto-Brightness.

You can also dim the screen manually in Control Centre, which does use less power.

But you might also forget to turn it back on, and you will be stuck squinting at a very low-power screen.

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This article originally appeared on Business Insider.