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What are your tips for preserving phone battery life?

A phone constantly running out of juice can be really annoying, especially if you’re out and about with no way to charge it. What do you do to preserve power?

I’m one of those people who uses their phone for absolutely everything, so the importance of battery life is key for me when it comes to picking a new phone.

See all our portable power bank charger reviews

But no matter how good your battery starts off, it will end up degrading over time. So, inspired by a recent Which? magazine feature, I want to know what your top tips are for preserving your phone’s power for as long as possible.

Battery power tips

In the November issue of Which?, our experts rounded up their own top five:

🔋 Control the screen brightness: The Number one cause of battery drain is your phone’s screen. Make sure it’s not turned up to full brightness. Somewhere between 65% and &-% brightness should still be readable.

🔋 Speed up auto-lock: Your screen will automatically lock after a certain amount of inactivity. The quicker it does the more battery life you’ll save. Set your smartphone to time out after one minute of inactivity.

🔋 Turn off power hungry features: Certain features guzzle battery life – for example wi-fi connections, location services and Bluetooth. Turn them off when you don’t need them, use airplane mode or turn your phone off if things are getting critical.

🔋Use Wi-Fi when streaming video: Wi-Fi is more power efficient than 3G or 4G. Using wi-fi also means the video is less likely to buffer and cause irritating breaks in your video playback.

🔋 Make use of battery optimisation features: Newer versions of iOS and Android have features to help battery life, including battery-saving modes, and better control for apps to prevent them from draining battery when they’re not being used.

And here’s one of my own tips: limit how many notifications you get. Constant push notifications making the phone vibrate, run apps in the background and wake the screen can be another drain on your battery life – not to mention annoying!

Limiting notifications can also help cut down on your screen time if you think you’re spending too much time on your phone.

Those are our tips (and one of mine!), but what are yours? How do you make your phone last longer and preserve its power for when you really need it?

Share your tips in the comments.


I carry a small powerbank to charge my phone if I am out for the day. What uses most power is tethering my laptop to use it online.

Powerbanks contain powerful lithium batteries and Which? found dangerous powerbanks and phone chargers on sale via AliExpress, Amazon Marketplace, eBay and Wish. https://www.which.co.uk/news/2019/09/killer-chargers-travel-adaptors-and-power-banks-rife-on-online-marketplaces/

I suppose it depends upon what everyday use you make of your phone and, if you are out all day for leisure, why you need to use your phone a lot. When I am out it often involves a car, so I keep a charger there. If I was away from the car all day and concerned about losing touch if I over-used my smart phone, I’d also carry my simple small payg phone as well. My concern would only be to retain the ability to message and make calls.

I suppose you could also turn your phone off until you need to use it.

As a dinosaur, I think we can be over-dependent on a mobile phone. However, if we are, we presumably replace them frequently. So why not just keep the previous model and use it as a back up?

I have an old Nokia C2-01 phone as a back-up. It was my only mobile before I bought a smartphone in 2014. Normally it lives in the car in case I go out without my smartphone. I take it with me when I travel by train.

I keep my smartphone turned off until I wish to use it. I always take it with me when I go out but have rarely had to use it, but it was handy when I was in hospital a year ago. Its main use is to receive one-time pass codes for payment transactions. I have never bothered to connect it to the internet.

Kevin says:
14 March 2022

I keep WiFi off unless I explicitly need it (eg when recharging to get latest AV and updates) and have also turned WiFi scanning off. The battery is good for over a week on a single charge, (discharge rate about 10%/day). I recharge once it’s less than 20% (apparently best for battery life).

Samsung did not support any further releases of Android on my model after the year of it’s release, which I find astonishing, having bought Samsung kit for years mostly on their reputation for quality and implied support.

Despite the impressive battery life, it’s the last Samsung device I will buy due to their lack of even the most basic firmware support.

Dr WiFi says:
18 March 2022

For lithium-based batteries you don’t ever want to go below 20% charged. It’s the extremes of high and low charge that cause damage.

If you want to check these fact just go to batteryuniversity.com, Apple, Microsoft, any lithium battery manufacturer or laptop manufacturer. Interrstingly, many laptops have an advanced BIOS setting to allow you to prevent the lithium battery being charged more than 80%… this is to protect the battery from damage.

Kevin says:
18 March 2022

Hi Dr WiFi
that’s useful information, just to clarify, I aim to charge the battery when it’s heading to 20%, I don’t run it significantly below that, but don’t recharge when it’s much above 20%. 5 years on I haven’t noticed any reduction in capacity, but that’s just a one device.

Since I would typically just plug the device in and let it charge to it’s built in limit rather than monitor it, the less often this cycle occurs (because I run it to fairly low charge), then presumably less damage is done since it reduces the time and frequency that it’s at 100% charge?

Specific manufacturer recharging advice seems scarce. I did find this from Samsung NZ:
“lithium-ion batteries do best when kept above a 50 percent charge”
and Apple has this on their “Optimized Battery Charging” advice in IOS 13+:
“When the feature is enabled, your iPhone will delay charging past 80% in certain situations”.

Microsoft say: “keep the battery level between 20% and 80% several times a week instead of using your device for only a short amount of time, and then plugging it in to recharge the battery” and “The best way to extend battery life and performance is to drain the battery below 50 percent several times a week

So 80% seems an ‘optimum’ upper limit, but discharge level isn’t so clear, apart from advice on storing long term at about 50% charge.

Alice says:
15 March 2022

Not sure how much of a difference it actually makes.. but I’m terrible for leaving apps working in the background. When I swipe up on my iphone and close down the apps I’m not using, that seems to make things feel a bit better!

My iPhone shows the percentage of battery power used by each app. It’s in Settings > Battery. I presume that Androids have an equivalent feature.

I once found that an app was using considerable battery power in the background and promptly deleted it.

Running your phone on 2g instead 3 , 4 or 5g saves considerable power and discorages spam e mails etc, lets face it you are not using your smartphone features that need the higher networks most of the time, but if you do high energy use is inevitable. So if you mainly only make calls and text 2g is fine, and if you need to use apps like sat nav etc you can change setting to 4g and after you have reached your destination switch back to 2g……after all the facility to change networks is built into your phone so why not use it

I turn on flight mode while at home, while still connected to wifi. Any incoming calls or SMS are received via wifi calling. This significantly reduces battery usage.

I also avoid charging above 80% unless I really need the extra 20%. Keeping the battery at 100% for an extended time really harms lifespan of the battery.

I turned on WiFi calling when we had a discussion a couple of years ago, NFH. For me, it does not make any significant difference because I have a strong mobile network signal but it will help those who live in weak signal areas.

Faye southall says:
25 March 2022

Was in an Apple Store last week about my husbands iPhone battery. Husband thought the same that leaving it at 100% is damaging. He was told that when it hits 100% there’s absolutely no damage to the battery leaving it on. I However charge my phone before I sleep, once it charged I turn it off, mainly because I don’t want to be woken up by notifications and emails etc.

Dr WiFi says:
18 March 2022

A good medium to long term way to extend the run time of any appliance powered by a rechargable lithium battery is never to allow it be be fully charged of fully depleted. Electric cars do this by never going outside a real range of 40% to 80% charged and the car industry believes this will make them keep 80% of their original useful capacity after 20 years of use. For mobile phones- do not regularly charge above 80% and never go below 20%.

Ideally we’d still be part of a powerful trade block and mandate that all devices by default stick to such an “eco 80/20” regime, that way our devices would wear out or fail long before the battery gives up.

Ian says:
18 March 2022

If you on Google about lithium batteries you will see if you charge them to 80% and dont below about 30% the battery capacity will last years longer…typically 5 times longer..obviously you will.have to charge twice as many times so be careful (genle) with you coonector so you dont wear the coonector out.

Mrs J Thomas says:
18 March 2022

Interesting comments. i have just been fitted with hearing aids that make use of bluetooth for mobile phone calls (which had been well nigh impossible on my mobile before this). But it does look as if it is hammering the battery on the phone and the hearing aids.

– Some phones have battery-saving and ultra-battery-saving modes that disable most apps and processes while allowing phone calls and SMS messages. If you don’t need apps running (e.g., overnight) they much increase battery endurance.
– If you want to increase battery lifespan (before it needs replacing), don’t charge it to more than 80% except when you need a full charge. There are apps that notify you when charge exceeds a level you specify (e.g., AccuBattery for Android). You can only limit charging automatically on an Android phone if it is “rooted” (highly technical), though there is a plug-in gadget that does this for any phone.

I turn my phone off every night. I shared that with friends the other night and they were shocked to hear that, but it makes perfect sense. They couldn’t actually come up with a reason why not. What is the point of keeping it on overnight when you’re asleep? When I switch it on in the morning, it comes on right away and it doesn’t seem to be doing it any harm.

I would prefer to keep my phone nearby and switched on overnight in case of emergency. That is more important for those who don’t have a landline phone.

Dont wait for the screen timeout if you have finished a session. Sleep the screen with the side button!

David Hodges says:
20 March 2022

Dr WiFI is getting political when he/she says ‘Ideally we’d still be part of a powerful trade block’,
that is their personal opinion, I’m personally absolutely delighted we are no longer under the thumb of un-elected bureaucrats.

I’m puzzled, if its bad for a lithium phone battery to charge above 80% capacity why is there not an inbuilt cut off. When I put my phone on charge I don’t check the charge level for hours, sometimes not until the next day when it’s fully charges.

My phone is a £170 Motorola G7 Power and the 5,000.0 mAh battery lasts 2-3 days. I bought it nearly 3 years ago, mainly for the long battery life as I was fed up with the battery life of my previous phone. I still carry my old Nokia 108 for emergencies and it fits neatly in my purse so it’s always with me. I charge it about every 10 – 14 days but I have never had to use it.

If you charge a lithium battery to 100% of its capacity it runs for longer before it goes flat (which is also bad for the battery). As you say, you want long battery life – between recharges I assume. Run time is a criterion consumers use to decide what phone to buy initially. Those on contracts in particularl aren’t interested in the lifetime of the phone as they will get a new one in two years. Manufacterers will design phones that customers want to buy.

If you only charge to 80%, and avoid fully discharging it, the overall lifetime of the battery will improve, but you will have to charge it more often. It also means the phone has less capacity for the same weight; the battery is the heaviest component.

Crusader says:
26 March 2022

I think you’ll find that with a lithium-ion battery, which it will be, there will be a cut off at some point as they have to cut off when charged to a point which is critical, or else they can become dangerous. But I don’t know what the charge percentage will be at that point as they have to cut off at a point which is safest and that won’t necessarily be where you’d prefer it to be.

Because I purchased quite an inexpensive phone it will be more convenient for me to charge the phone to 100% and replace it when the battery starts to run down too quickly. I like my phone and would happily stick with it after that if the battery was replaceable like my old phones. Why do we get rid of a perfectly working phone because the battery runs down too quickly.

Modern phones are designed to protect their batteries from overcharging and excessive discharge of their batteries. It is possible to maximise their life, as explained in this discussion but batteries do have a limited life.

Few modern smartphones have user-replaceable batteries because manufacturers want to sell more phones. This must change and we should go back to phones with replaceable batteries.

This is an over-simplistic view perhaps. Some pros and cons are given here https://timesofindia.indiatimes.com/gadgets-news/explained-why-modern-smartphones-dont-have-removable-batteries-and-how-does-it-affect-consumers/articleshow/89119202.cms

I would like, in principle, to see replaceable batteries or to see phones sold refurbished with professionally installed replacement batteries. However, if batteries have a sufficiently long life then that would substantially reduce the problem.

Total phone life is the core issue. Many have very short lives before security and usefulness is compromised by the withdrawal of security updates. Even 5 years (many are less) for many users is too short. Until this is addressed, which for many seems to render the phone useless, non-replaceable batteries seems a side issue.

Malcolm – I’m not aware that not having the latest security updates reduces a phone’s usefulness. I have challenged the Which? position on the vulnerability of older phones without security updates a number of times and never had a satisfactory response. I don’t know who has taken over from Kate, but maybe we can get a balanced view of the risks, as things have moved on since Android 10.

I will ignore Apple – which I no nothing about – but they would not feature in a list of cheaper phones that someone just wanting basic features would buy and keep for life.

It is true that phone manafacturers have been rather economical with the number of Android updates they deploy for their phones, but the Google (Android developers) have been restructuring their software to ensure some core security patches are delivered through PlayStore. These are independent of the OEM updates.

If you have a modern Android phone (mine is an S21 which Samsung undertake to support for at least 4 years anyway), I have two sets of security patches deployed. You can check a modern Android (Version 10+) phone for this as follows:

Go to Settings > About phone > Software information.

Mine shows a Google Play system update: 1 January 2022. This is the patch delivered directly from Google Playstore.

Android security patch level update: 1 March 2022. This is the patch that Samsung deploy.

Having a modern phone even with all the latest patches installed can give users a false sense of security about the need to be alert and take sensible precautions.

From Android Central:

“It’s not exactly feasible to roll out a new software update for each and every vulnerability. Most bugs and security loopholes are pretty minor and will likely not affect the vast majority of individuals immediately. Furthermore, researchers don’t typically make exploits publicly known until a patch is released. This is known as responsible disclosure.”

Vulnerabilities are highly technical and can be difficult to monetize. Why bother, when shoulder surfing in a crowded place or using 1234 as a pin code will offer a £100 tap-to-pay bonus for anyone removing your phone from a hip pocket or bag. That will have an immediate effect and drastically shorten the usable life of your phone.

The Times of India article makes an interesting point that the tracking function of a mobile phone cannot be easily disabled if the battery is sealed. This means you may have more chance of locating it before the battery runs down of its own accord, if the aforementioned theft has taken place and you notice in time.

Not being a tea-leaf myself, it hadn’t occurred to me to remove the batteries when stealing a phone.

Screens are usually glued in place on modern smartphones and have to be heated near the edges and prised off to replace the battery. This improves water resistance but is difficult for anyone without experience. Manufacturers may not sell replacement batteries, so when I wanted to replace the battery in my five year old iPhone I had to buy a compatible battery. It worked fine to start with but failed within a couple of months.

Support for phones can be extended but since manufacturers want to sell more phones, legislation is needed.

Em, thanks. There is an article by Amy Axworthy in the April Which? mag that continues the Which? advice that lack of security updates renders your phone far more susceptible to “Global cyberattacks” and “ransomware attacks”. They have in the past pointed out vulnerability when using them for banking. This advice no doubt persuades many that they need to renew their phone when support stops and thus contributes heavily to waste.

If what you imply is correct then perhaps you should discuss with Which? to get their future advice modified.

I have an old Samsung S4. A number of useful apps – the NHS askfirst for example – do not work. This is not down to non-existent security updates but old software. Why cannot quite essential apps like this be designed for for older software (it is not a criticism but a question)?

Crusader says:
27 March 2022

Sometimes the phone’s internal charging regulator fails but the phone still works otherwise, but is rendered useless because you can longer charge it, no matter how good the battery is. That’s what happened to an alcatel “simple to use” phone which I had which I had to dump because it’s regulator failed but I didn’t know that at first, I could see that the battery had visibly failed as it was misshapen and I couldn’t get a replacement here in the UK so I had to import one from Berlin which luckily wasn’t that expensive but when I fitted it in my phone and tried charging it wouldn’t work, even with other USB chargers, so the phone’s internal regulator must’ve failed, so the phone was no longer usable. So now I’m left with a good new battery which is no use. So surely the same must happen to some “smart” phones too as it’s common practice with such devices to fit the necessary regulating device inside the phone rather than in the charger, and of course such a regulator is not user replaceable, it’s a professional job.

It’s rotten to put in time and money to do a repair and it does not work. 🙁 I don’t know how often charge controllers fail in phones but there are good reasons to have them in phones rather than chargers. The management of charging is specific to the phone and there will be a temperature sensor to monitor the battery temperature. As batteries near completion of a charge cycle, more energy is dissipated as heat and the charge rate must be reduced or stopped to prevent damage.

Scottie says:
29 March 2022

Surely the circuitry in modern phones could be programmed to charge to the best level then cut off. I have a fairly inexpensive Galaxy A22 which notifies me when to plug in the charger (about 22%) and slows the rate of charge, from fast charge at about 75%, to a trickle charge.

That’s right. The battery charges quickly to start with and then the charge rate reduces, which avoids overheating and damage.

Why then are people charging their phones to 80% only when the battery is protected. I use battery saver, if running low, when I’m out and about to ensure I do not run out of charge but always charge it to the maximum. I bought my phone because of it’s long battery life and take advantage of that. If I had paid iPhone prices I might have a different view.