Technologies

The Truth Behind Always Charging Your Phone and Battery Life Explained

Here’s the science behind your phone’s battery life. Apple, Google and Samsung weigh in on best practices.

In the not-so-distant past smartphone users were told not to leave their phones plugged in overnight or it could do serious damage to the battery. While current smartphone models now have protection from accidentally overcharging, plenty of folks still have questions about whether charging their devices for extended periods of time will damage the battery.

The short answer is no. Keeping your phone plugged in all the time won’t ruin your battery. Modern smartphones are built with smart charging systems that cut off or taper power once they’re full, preventing the kind of «overcharging damage» that was common in older devices. So if you’re leaving your iPhone or Android on the charger overnight, you can relax.

That said, «won’t ruin your battery» doesn’t mean it has no effect. Batteries naturally degrade with age and use, and how you charge plays a role in how fast that happens. Keeping a phone perpetually at 100% can add extra stress on the battery, especially when paired with heat, which is the real enemy of longevity.

Understanding when this matters (and when it doesn’t) can help you make small changes to extend your phone’s lifespan.

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The science behind battery wear

Battery health isn’t just about how many times you charge your phone. It’s about how it manages voltage, temperature and maintenance. Lithium-ion batteries age fastest when they’re exposed to extreme levels: 0% and 100%.

Keeping them near full charge for long stretches puts additional voltage stress on the cathode and electrolyte. That’s why many devices use «trickle charging» or temporarily pause at 100%, topping up only when needed.

Still, the biggest threat isn’t overcharging — it’s heat. When your phone is plugged in and running demanding apps, it produces heat that accelerates chemical wear inside the battery. If you’re gaming, streaming or charging on a hot day, that extra warmth does far more harm than leaving the cable plugged in overnight.

Apple’s take

Apple’s battery guide describes lithium-ion batteries as «consumable components» that naturally lose capacity over time. To slow that decline, iPhones use Optimized Battery Charging, which learns your daily routine and pauses charging at about 80% until just before you typically unplug, reducing time spent at high voltage.

Apple also advises keeping devices between 0 to 35 degrees Celsius (32 to 95 degrees Fahrenheit) and removing certain cases while charging to improve heat dissipation. You can read more on Apple’s official battery support page.

What Samsung (and other Android makers) do

Samsung offers a similar feature called Battery Protect, found in One UI’s battery and device care settings. When enabled, it caps charging at 85%, which helps reduce stress during long charging sessions.

Other Android makers like Google, OnePlus and Xiaomi include comparable options — often called Adaptive Charging, Optimized Charging or Battery Care — that dynamically slow power delivery or limit charge based on your habits. These systems make it safe to leave your phone plugged in for extended periods without fear of overcharging.

When constant charging can hurt

Even with these safeguards, some conditions can accelerate battery wear. As mentioned before, the most common culprit is high temperature. Even for a short period of time, leaving your phone charging in direct sunlight, in a car or under a pillow can push temperatures into unsafe zones.

Heavy use while charging, like gaming or 4K video editing, can also cause temperature spikes that degrade the battery faster. And cheap, uncertified cables or adapters may deliver unstable current that stresses cells. If your battery is already several years old, it’s naturally more sensitive to this kind of strain.

How to charge smarter

You don’t need to overhaul your habits but a few tweaks can help your battery age gracefully.

Start by turning on your phone’s built-in optimization tools: Optimized Battery Charging on iPhones, Battery Protect on Samsung devices and Adaptive Charging on Google Pixels. These systems learn your routine and adjust charging speed so your phone isn’t sitting at 100% all night.

Keep your phone cool while charging. According to Apple, phone batteries perform best between 62 and 72 degrees Fahrenheit (16 to 22 degrees Celsius). If your phone feels hot, remove its case or move it to a better-ventilated or shaded spot. Avoid tossing it under a pillow or too close to other electronics, like your laptop, and skip wireless chargers that trap heat overnight.

Use quality chargers and cables from your phone’s manufacturer or trusted brands. Those cheap «fast-charge» kits you find online often deliver inconsistent current, which can cause long-term issues.

Finally, don’t obsess over topping off. It’s perfectly fine to plug in your phone during the day for short bursts. Lithium-ion batteries actually prefer frequent, shallow charges rather than deep, full cycles. You don’t need to keep it between 20% and 80% all the time, but just avoid extremes when possible.

The bottom line

Keeping your phone plugged in overnight or on your desk all day won’t destroy its battery. That’s a leftover myth from a different era of tech. Modern phones are smart enough to protect themselves, and features like Optimized Battery Charging or Battery Protect do most of the heavy lifting for you.

Still, no battery lasts forever. The best way to slow the inevitable is to manage heat, use quality chargers and let your phone’s software do its job. Think of it less as «babying» your battery and more as charging with intention. A few mindful habits today can keep your phone running strong for years.

Technologies

Google, Meta and Amazon Join Global Pact to Fight Rising Online Scams

The companies will share fraud intelligence and coordinate responses as AI makes scams faster, cheaper and harder to detect.

Modern online scams operate across multiple platforms, perhaps spanning social media, messaging apps, email and online marketplaces. Google, Meta and Amazon are among 11 tech, retail and payments companies that have signed a new agreement to combat online scams by sharing threat intelligence across platforms, Axios first reported Monday.

The initiative, called the Industry Accord Against Online Scams & Fraud, is designed to improve how companies detect and respond to fraud that spans multiple services. Participants say they will exchange signals, such as scam-linked accounts and fraudulent domains, and coordinate enforcement actions.

By sharing intelligence in near real time, companies hope to identify these scams earlier and stop them before they spread.

The effort reflects how modern scams operate. A victim might encounter a fake celebrity investment ad on social media, move to a messaging app where the scammer builds trust, then faces prompts to send money through a fraudulent website, payment app or crypto wallet — spanning multiple companies’ ecosystems.

Google said it now blocks hundreds of millions of scam-related results every day using AI, underscoring how both attackers and defenders are increasingly relying on the same technology. Meta removed more than 159 million scam ads in 2025 and is expanding AI tools to detect impersonation and warn users.

Online scams are growing rapidly, in part because generative AI has lowered the barrier to entry. AI can be used not only to produce realistic phishing emails but also to clone voices and deepfake videos that impersonate executives, public figures and even family members.

The agreement is voluntary and doesn’t create new legal obligations, but it comes after regulators’ increased pressure on tech platforms to address fraud more aggressively. The companies say they will begin building frameworks for reporting and intelligence-sharing, though it’s not yet clear how quickly those systems will be deployed or how effective they will be in practice.

Technologies

Today’s NYT Mini Crossword Answers for Wednesday, March 18

Here are the answers for The New York Times Mini Crossword for March 18.

Looking for the most recent Mini Crossword answer? Click here for today’s Mini Crossword hints, as well as our daily answers and hints for The New York Times Wordle, Strands, Connections and Connections: Sports Edition puzzles.

Need some help with today’s Mini Crossword? I thought it was a fairly easy one, but read on for all the answers. And if you could use some hints and guidance for daily solving, check out our Mini Crossword tips.

If you’re looking for today’s Wordle, Connections, Connections: Sports Edition and Strands answers, you can visit CNET’s NYT puzzle hints page.

Read more: Tips and Tricks for Solving The New York Times Mini Crossword

Let’s get to those Mini Crossword clues and answers.

Mini across clues and answers

1A clue: Word before «card,» flood» or «photography»
Answer: FLASH

6A clue: Joust weapon
Answer: LANCE

7A clue: Brain, heart or lungs
Answer: ORGAN

8A clue: «Frozen» reindeer
Answer: SVEN

9A clue: What can be found on frozen roads or frozen margaritas
Answer: SALT

Mini down clues and answers

1D clue: Follow a dentist’s recommendation
Answer: FLOSS

2D clue: Baby bug
Answer: LARVA

3D clue: Shape made in the snow
Answer: ANGEL

4D clue: Very little
Answer: SCANT

5D clue: Egg layer
Answer: HEN

Technologies

Amazon Speeds Up Delivery Even More With 1- and 3-Hour Options

The retailer says the one-hour option is available in hundreds of cities, with discounted shipping for Prime members.

Same-day delivery apparently isn’t fast enough for some Amazon shoppers. The retail giant said on Tuesday it’s adding new shipping options that will get products to front doors within a one- or three-hour window.

The company said in its announcement that the one-hour option is available in hundreds of cities across the US, while the three-hour option is now live in more than 2,000 areas. Amazon’s web page at amazon.com/getitfast shows whether those options are available to shoppers for their location. More than 90,000 products will be available for those shipping windows, the company said.

For those who can’t get those services (including the author of this post, who lives between Austin and San Antonio in Texas), a message will display: «3-hour delivery is currently unavailable. Check back at a later time or shop products with Same-Day delivery below.»

Pricing for the faster delivery options is not cheap: It’ll cost you $20 for one-hour delivery and $15 for three-hour delivery for those without an Amazon Prime account, or $10 and $5 for customers who subscribe to Prime.

Last year, the company rolled out faster Amazon delivery options to 4,000 additional areas.

In a video of the podcast Learn and Be Curious with Doug Herrington, hosted by Amazon’s CEO of worldwide stores, Kandace Kapps, the director of the company’s same-day strategy team, spoke in more detail about the challenges of fast shipping. Kapps discussed shifts in customer buying habits over the last few years, such as more people buying household essentials like toilet paper on Amazon.

She said that Amazon can deliver so quickly by placing same-day delivery hubs close to customers in metro areas and by getting products ready to ship within 15 minutes, aided by warehouse robots.

«I think customers are going to continue to get magically surprised by how fast we can deliver to their doorstop,» Kapps said.

Herrington said fast shipping increases sales: «When we speed up the service, the probability that somebody buys a product from us goes up.»

Other retailers, including Walmart, have been adding same-day delivery options or exploring other ways to speed up shipping times to compete with Amazon.

Removing buyers’ moments of hesitation

Part of Amazon’s strategy, which has involved a massive buildout of locations, deployment of thousands of trucks, deals with other delivery services and investment in logistics software, is actually pretty simple: being there when people need last-minute items or make impulse buys.

«It’s about removing the last moment where you would’ve reconsidered the purchase,» said Stephanie Carls, retail insights expert at coupon and promotional-code website RetailMeNot, a sibling site of CNET. «It changes how you shop, not just how fast you get things.»

Carls said that Amazon’s super-fast delivery is removing the timeframe when people might change their minds about a purchase.

«There used to be a gap between deciding to buy something and actually having it. That’s when you’d price check, rethink it, or decide you didn’t need it after all,» she said. «This closes that gap.»

The retail expert said that competitors, including Walmart and Target, have been speeding up delivery times in some markets. Still, they’re not matching Amazon’s scale or product range at those speeds or levels of consistency.

«And that’s what starts to make everyone else feel slow,» Carls said. «Amazon’s advantage is how tightly connected its technology, inventory and delivery networks are, which makes this level of speed more repeatable.»