Have you been thinking, "My phone feels slower lately," or "It was at 100% this morning, but it is already down to 30% by lunch"?

The other day, my mom's iPhone started showing the same symptoms. When I checked it, the battery's maximum capacity had dropped to 72%. She had been using it for five years, so it was probably time to replace it. But when she asked, "So how many years should you use a phone before replacing it?" I realized I did not have a very clear answer.

According to the Cabinet Office's Consumer Confidence Survey conducted in December 2023, the average smartphone is used for 4.4 years. About 70% of people replace their phones somewhere between three and five years. That said, this is only an average. The real right time to replace your phone depends on things like battery wear and how long the operating system is still supported.

In this article, we will use the latest information available as of April 2026 to explain six signs that it may be time to replace your smartphone, plus the steps you should take before switching to a new device.

How many years does a smartphone last? Think about it in terms of battery life and OS support

When people talk about a smartphone's "lifespan," they are usually talking about two different things.

The first is battery lifespan. The lithium-ion batteries used in smartphones gradually wear down each time they are charged and discharged. As a general guideline, maximum capacity drops to around 70% to 80% after 300 charge cycles, and to around 50% to 70% after 500 cycles. If you charge your phone every day, many people start to feel battery degradation after about two to three years.

The second is OS support lifespan. Once your phone can no longer update to the latest OS, it stops receiving some security fixes, and apps gradually stop supporting it as well.

  • iPhone: A rough guideline is about five to six years from release. With iOS 26 in fall 2025, the iPhone XS and XR were dropped from support
  • Android: It depends on the manufacturer and model, but two to four years is common. Recently, though, phones are lasting longer, with Google's Pixel series guaranteeing seven years of OS updates

In other words, if you look only at the battery, a smartphone's lifespan is about two to three years. If you include OS support, it is fair to think of three to five years as the practical lifespan of a smartphone.

6 signs it may be time to replace your phone

Sign 1: The battery drains unusually fast, especially if maximum capacity is below 80%

If you fully charge your phone in the morning and it is below 20% by evening, and that keeps happening, your battery has probably worn down quite a bit.

The key number to watch is 80% maximum capacity. Apple Support also treats battery capacity below 80% as a point where you should consider battery service or replacement. Starting with the iPhone 15 lineup, Apple improved the battery materials and raised the benchmark to "retain 80% capacity at 1,000 complete charge cycles," while earlier models use 500 cycles as the guideline.

How to check maximum battery capacity:

  • iPhone: Go to "Settings" -> "Battery" -> "Battery Health & Charging" to check maximum capacity. On iPhone 15 and later, you can also see the charge cycle count there
  • Android (Galaxy): Go to "Settings" -> "Battery and device care" -> "Battery" -> "Battery status"
  • Android (Pixel): Go to "Settings" -> "Battery" to check battery usage. For more detail, a diagnostic app such as "AccuBattery" can be helpful

Sign 2: The phone feels sluggish or apps take a long time to open

If LINE takes more than five seconds to open, the camera app launches slowly, or text conversion suggestions lag while you type, that sluggish feeling is a sign that your phone's performance is no longer keeping up with what modern apps require.

Apps get a little heavier every year as they are updated. On a phone from three or four years ago, it can become difficult to run the latest versions smoothly. Low storage can also slow things down, especially if you have less than 10% free space, so try deleting unnecessary photos and apps first. If that does not help, it may be time to replace the phone.

Sign 3: Apps crash or freeze frequently

If many different apps suddenly close, or the screen freezes and stops responding, the cause is often not one specific app. It may be a lack of memory (RAM) or aging storage.

More and more modern apps are designed with 4GB or more of RAM in mind. Entry-level phones from three or four years ago often have around 3GB of RAM, and they can struggle when you use several apps at the same time.

Sign 4: OS updates have stopped arriving

This is easy to overlook, but it is the most serious warning sign from a security standpoint. Once OS updates end, newly discovered security vulnerabilities, meaning weaknesses that can be used by attackers, no longer get fixed.

As of April 2026, check whether your iPhone supports iOS 26, or whether your Android phone has received a security update within the past year.

How to check:

  • iPhone: Go to "Settings" -> "General" -> "Software Update" and see whether you can update to the latest version
  • Android: Go to "Settings" -> "Security & privacy" -> "System & updates" and check the security patch date. If it is more than a year old, be careful

Sign 5: Charging takes unusually long or stops partway through

If your phone used to fully charge in an hour and a half but now takes three hours, or if it barely moves past 80%, that can also be a sign of battery degradation. A worn-out charging cable or adapter can cause the same problem, so try a different cable first. If changing the cable does not help, the battery itself is likely the issue.

Sign 6: The phone gets unusually hot

If your phone gets hot while you are only watching videos, or becomes almost too hot to touch while charging, the cause may be battery degradation or excessive load on the processor. Heat also accelerates further battery wear, creating a bad cycle, so if it happens often, it is better to replace the phone sooner rather than later.

Battery replacement or a new phone? Use these 3 criteria to decide

You may be wondering, "Could I keep using it if I just replace the battery?" Here are three ways to decide.

1. Is the OS still supported?
If the phone is still within its support period, replacing the battery can be worth it. On the other hand, if support has already ended, a new battery will not solve the underlying problem: security risk.

2. The cost of battery replacement versus a new phone
As of April 2026, official Apple battery service starts at 11,200 yen for models from iPhone SE through the iPhone 14 series. For Android phones, the cost varies by manufacturer and model, but is often around 5,000 to 15,000 yen. If you have been using the phone for more than four years and are also seeing other symptoms like sluggish performance or freezing, replacing the whole phone is often the better value overall.

3. Whether the phone is powerful enough for what you want to do
If all you use is email and LINE, an older phone may still be enough. But if you want to play the latest games or edit 4K video, replacing it is the clear choice. A freelancer friend once mentioned during a Zoom call that "old phones freeze during screen sharing," and people who use their phones for work tend to feel performance limits sooner.

5 things to do before switching phones: a checklist to prevent data loss

Once you decide to replace your phone, do the following before you get your new phone. These are all things I wished we had handled earlier when helping my mom switch devices.

Step 1: Back up photos and videos

For iPhone, check your iCloud backup. For Android, check automatic backup in Google Photos. If you do not have enough storage, you can import files to a computer or temporarily upgrade your cloud storage plan.

Step 2: Back up LINE chat history and turn on account transfer

With LINE, there are many cases where chat history disappears if account transfer is not turned on. Go to "Settings" -> "Account transfer" and turn it on, and do not forget to back up your chat history as well. The backup destination is iCloud or Google Drive.

Step 3: Back up authenticator apps such as Google Authenticator and Microsoft Authenticator

If you use an authenticator app for two-factor authentication, losing it during a phone switch can lock you out of your services. For Google Authenticator, turn on "sync to Google Account." For Microsoft Authenticator, check your cloud backup settings.

Step 4: Move Mobile Suica or PASMO to the server

For transit IC cards, it is essential to move the card to the server from your old device first, then receive it on the new device. If you switch phones without doing this, you may not be able to use it at the ticket gate. You can do this from the Wallet app on iPhone or the Osaifu-Keitai app on Android.

Step 5: Check IDs and passwords for each service

You may be surprised how many services require you to log in again on a new phone. Make sure you know the passwords for your Apple ID or Google Account, banking app login information, and anything else you will need. If you use a password manager, make absolutely sure you remember its master password.

Want your phone to last longer? 3 tips for extending battery lifespan

If you want to keep using your current phone a little longer, or make your new phone last as long as possible, these habits can help slow battery degradation.

1. Keep the battery between 20% and 80%
Lithium-ion batteries wear out faster when you drain them to 0% or leave them sitting at 100%. Recent iPhones (iOS 13 and later) and many Android phones have an "optimized charging" feature that automatically pauses charging around 80%. Check whether "Optimized Battery Charging" is turned on under "Settings" -> "Battery."

2. Avoid hot environments
Do not leave your phone in a car under direct sunlight, and avoid charging it on top of bedding. Lithium-ion batteries are sensitive to heat, and degradation speeds up rapidly in environments above 45 degrees Celsius. In summer, it helps to take your phone out of your pocket and place it in the shade, or remove the case so heat can escape.

3. Avoid using the phone for long periods while charging
Playing games or watching videos while charging makes the phone charge and discharge at the same time, placing a heavy load on the battery. Simply getting into the habit of leaving your phone alone while it charges, then using it after charging is done, can make a difference in how long the battery lasts.

FAQ

Can replacing only the smartphone battery extend its lifespan?

Battery replacement can restore battery life, but it does not solve problems with processing speed or OS support. If you have used the phone for less than three years and OS support is still ongoing, replacement can be worth it. If it has been four years or more, a new phone is usually the better choice.

Which lasts longer, iPhone or Android?

As a general guideline, iPhone OS support lasts five to six years, while Android support is often two to four years, with some models offering up to seven years. That said, recent Pixel and Galaxy S series phones now offer long-term support, so it depends a lot on the model you choose.

How should I dispose of an old smartphone?

The three main options are carrier trade-in, manufacturer recycling programs, and used-device buyback shops. Before disposing of the phone, always erase it by restoring factory settings, and remove the SIM card and SD card.

Do budget smartphones have the same lifespan?

There is not a huge difference in hardware durability, but the OS update period varies by manufacturer. Before buying, it is a good idea to check the manufacturer's official website to see how many years of OS updates are guaranteed.

What month is the best time to replace a phone?

Right after new models launch is often a good time, because older models tend to get discounted. For iPhone, that is usually around September, while Android launches are common in spring and fall. March end-of-fiscal-year sales and carrier switching campaigns can also be good opportunities.

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