Understand iPhone performance and its relation to your battery.
Your iPhone is designed to deliver an experience that is simple and easy to use. This is only possible through a combination of advanced technologies and sophisticated engineering. One important technology area is battery and performance. Batteries are a complex technology, and a number of variables contribute to battery performance and related iPhone performance. All rechargeable batteries are consumables and have a limited lifespan—eventually their capacity and performance decline such that they need to be replaced. As batteries age, it can contribute to changes in iPhone performance. We created this information for those who would like to learn more.
About lithium-ion batteries
iPhone batteries use lithium-ion technology. Compared with older generations of battery technology, lithium-ion batteries charge faster, last longer, and have a higher power density for more battery life in a lighter package. Rechargeable lithium-ion technology currently provides the best technology for your device. Learn more about lithium-ion batteries.
How to maximize battery performance
“Battery life” is the amount of time a device runs before it needs to be recharged. “Battery lifespan” is the amount of time a battery lasts until it needs to be replaced. One factor affecting battery life and lifespan is the mix of things you do with your device. No matter how you use it, there are ways to help. A battery’s lifespan is related to its “chemical age,” which is more than just the passage of time. It includes different factors, such as the number of charge cycles and how it was cared for. Follow these tips to maximize battery performance and help extend battery lifespan. For example, keep iPhone half-charged when it’s stored for the long term. Also avoid charging or leaving iPhone in hot environments, including direct sun exposure, for extended periods of time.
When batteries chemically age
All rechargeable batteries are consumable components that become less effective as they chemically age.
As lithium-ion batteries chemically age, the amount of charge they can hold diminishes, resulting in shorter amounts of time before a device needs to be recharged. This can be referred to as the battery’s maximum capacity—the measure of battery capacity relative to when it was new. In addition, a battery’s ability to deliver maximum instantaneous performance, or “peak power,” may decrease. In order for a phone to function properly, the electronics must be able to draw upon instantaneous power from the battery. One attribute that affects this instantaneous power delivery is the battery’s impedance. A battery with a high impedance may be unable to provide sufficient power to the system that needs it. A battery's impedance can increase if a battery has a higher chemical age. A battery’s impedance will temporarily increase at a low state of charge and in a cold temperature environment. When coupled with a higher chemical age, the impedance increase will be more significant. These are characteristics of battery chemistry that are common to all lithium-ion batteries in the industry.
When power is pulled from a battery with a higher level of impedance, the battery’s voltage will drop to a greater degree. Electronic components require a minimum voltage to properly operate. This includes the device’s internal storage, power circuits, and the battery itself. The power management system determines the capability of the battery to supply this power, and manages the loads in order to maintain operations. When the operations can no longer be supported with the full capabilities of the power management system, the system will perform a shutdown to preserve these electronic components. While this shutdown is intentional from the device perspective, it may be unexpected by the user.
Preventing unexpected shutdowns
With a low battery state of charge, a higher chemical age, or colder temperatures, users are more likely to experience unexpected shutdowns. In extreme cases, shutdowns can occur more frequently, thereby rendering the device unreliable or unusable. For iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPhone SE (1st generation), iPhone 7, and iPhone 7 Plus, iOS dynamically manages performance peaks to prevent the device from unexpectedly shutting down so that the iPhone can still be used. This performance management feature is specific to iPhone and does not apply to any other Apple products. Starting with iOS 12.1, iPhone 8, iPhone 8 Plus, and iPhone X include this feature; iPhone XS, iPhone XS Max, and iPhone XR include this feature starting with iOS 13.1. The effects of performance management on these newer models may be less noticeable due to their more advanced hardware and software design.
This performance management works by looking at a combination of the device temperature, battery state of charge, and battery impedance. Only if these variables require it, iOS will dynamically manage the maximum performance of some system components, such as the CPU and GPU, in order to prevent unexpected shutdowns. As a result, the device workloads will self-balance, allowing a smoother distribution of system tasks, rather than larger, quick spikes of performance all at once. In some cases, a user may not notice any differences in daily device performance. The level of perceived change depends on how much performance management is required for a particular device.
In cases that require more extreme forms of this performance management, the user may notice effects such as:
Longer app launch times
Lower frame rates while scrolling
Backlight dimming (which can be overridden in Control Center)
Lower speaker volume by up to -3dB
Gradual frame rate reductions in some apps
During the most extreme cases, the camera flash will be disabled as visible in the camera UI
Apps refreshing in background may require reloading upon launch
Many key areas are not impacted by this performance management feature. Some of these include:
Cellular call quality and networking throughput performance
Captured photo and video quality
Sensors like gyroscope, accelerometer, barometer
For a low battery state of charge and colder temperatures, performance management changes are temporary. If a device battery has chemically aged far enough, performance management changes may be more lasting. This is because all rechargeable batteries are consumables and have a limited lifespan, eventually needing to be replaced. If you are impacted by this and would like to improve your device performance, replacing your device battery can help.
For iOS 11.3 and later
iOS 11.3 and later improve this performance management feature by periodically assessing the level of performance management necessary to avoid unexpected shutdowns. If the battery health is able to support the observed peak power requirements, the amount of performance management will be lowered. If an unexpected shutdown occurs again, then performance management will increase. This assessment is ongoing, allowing more adaptive performance management.
iPhone 8 and later use a more advanced hardware and software design that provides a more accurate estimation of both power needs and the battery’s power capability to maximize overall system performance. This allows a different performance management system that more precisely allows iOS to anticipate and avoid an unexpected shutdown. As a result, the impacts of performance management may be less noticeable on iPhone 8 and later. Over time, the rechargeable batteries in all iPhone models will diminish in their capacity and peak performance and will eventually need to be replaced.
For iPhone 6 and later, iOS 11.3 and later add new features to show battery health and recommend if a battery needs to be replaced. These can be found in Settings > Battery > Battery Health.
Additionally, users can see if the performance management feature that dynamically manages maximum performance to prevent unexpected shutdowns is on and can choose to turn it off. This feature is enabled only after an unexpected shutdown first occurs on a device with a battery that has diminished ability to deliver maximum instantaneous power. This feature applies to iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPhone SE (1st generation), iPhone 7, and iPhone 7 Plus. Starting with iOS 12.1, iPhone 8, iPhone 8 Plus, and iPhone X include this feature; iPhone XS, iPhone XS Max, and iPhone XR include this feature starting with iOS 13.1. The effects of performance management on these newer models may be less noticeable due to their more advanced hardware and software design.
(Note: Devices updating from iOS 11.2.6 or earlier will initially have performance management disabled; it will be reenabled if the device subsequently experiences an unexpected shutdown.)
All iPhone models include fundamental performance management to ensure that the battery and overall system operates as designed and internal components are protected. This includes behavior in hot or cold temperatures, as well as internal voltage management. This type of performance management is required for safety and expected function, and cannot be turned off.
Your battery's maximum capacity
The Battery Health screen includes information on maximum battery capacity and peak performance capability.
Maximum battery capacity measures the device battery capacity relative to when it was new. A battery will have lower capacity as the battery chemically ages which may result in fewer hours of usage between charges. Depending upon the length of time between when the iPhone was made and when it is activated, your battery capacity may show as slightly less than 100%.
A normal battery is designed to retain up to 80% of its original capacity at 500 complete charge cycles when operating under normal conditions. The one-year warranty includes service coverage for a defective battery. If it is out of warranty, Apple offers battery service for a charge. Learn more about charge cycles.
As your battery health degrades, so can its ability to deliver peak performance. The Battery Health screen includes a section for Peak Performance Capability where the following messages may appear.
Performance is normal
When the battery condition can support normal peak performance and does not have the performance management features applied, you'll see this message:
Your battery is currently supporting normal peak performance.
Performance management applied
When the performance management features have been applied, you'll see this message:
This iPhone has experienced an unexpected shutdown because the battery was unable to deliver the necessary peak power. Performance management has been applied to help prevent this from happening again. Disable…
Note that if you disable performance management, you can’t turn it back on. It will be turned on again automatically if an unexpected shutdown occurs. The option to disable will also be available.
Battery health unknown
If iOS is unable to determine the device battery health, you'll see this message:
This iPhone is unable to determine battery health. An Apple Authorized Service Provider can service the battery. More about service options…
This may be due to having an improperly installed battery or an unknown battery part.
Performance management turned off
If you disable the applied performance management feature, you'll see this message:
This iPhone has experienced an unexpected shutdown because the battery was unable to deliver the necessary peak power. You have manually disabled performance management protections.
If the device experiences another unexpected shutdown, the performance management features will be re-applied. The option to disable will also be available.
Battery health degraded
If battery health has degraded significantly, the below message will also appear:
Your battery’s health is significantly degraded. An Apple Authorized Service Provider can replace the battery to restore full performance and capacity. More about service options…
This message does not indicate a safety issue. Your battery can still be used. However, you may be experiencing more noticeable battery and performance issues. A new replacement battery will improve your experience.
Important Battery Message
If you see the message below, it means the battery in your iPhone is unable to be verified. This message applies to iPhone XS, iPhone XS Max, iPhone XR, and later.
Unable to verify this iPhone has a genuine Apple battery. Health information not available for this battery. Learn more...
Reported battery health information is not available. To have your battery checked, contact an Apple Authorized Service Provider. More about service options.
Learn more about this message as it appears on iPhone 11 and iPhone 11 Pro.
Getting further assistance
If your device performance has been impacted by an aged battery and you would like to get help with a battery replacement, contact Apple Support for service options.
Learn more about battery service and recycling.
Learn how to set up your iPhone, iPad, or iPod touch.
If you're switching to a new device
If you want to transfer your information from another device to your new iPhone, iPad, or iPod touch, follow these steps:
From another iPhone, iPad, or iPod touch
From an Android device
Make sure that you back up your previous iOS device so that you can transfer the content to the new device.
If you're setting up your first iOS device
If you already set up your new device but want to start over, learn how to erase your iPhone, iPad, or iPod touch.
Otherwise, follow these steps:
Turn on your device
Press and hold the device's power button until you see the Apple logo. You'll then see "Hello" in many languages. Follow the steps to get started. If you're blind or have low vision, you can turn on VoiceOver or Zoom from the Hello screen.
When asked, choose your language. Then tap your country or region. This affects how information looks on your device, including date, time, contacts, and more. At this point, you can tap the blue accessibility button to set up Accessibility Options that can optimize your setup experience and the use of your new device.
Get help if your iPhone, iPad, or iPod touch won't turn on, or if your device is disabled or requires a passcode.
If you have another device, use Quick Start
If you have another device, you can use it to automatically set up your new device with Quick Start. Bring the two devices close together, and then follow the instructions.
If you don’t have another device, tap "Set Up Manually" to continue.
Activate your device
You need to connect to a Wi-Fi network, a cellular network, or iTunes to activate and continue setting up your device.
Tap the Wi-Fi network that you want to use or select a different option. If you're setting up an iPhone or iPad (Wi-Fi + Cellular), you might need to insert your iPhone SIM card or iPad SIM card first.
Get help if you can't connect to Wi-Fi or if you can't activate your iPhone.
Set up Face ID or Touch ID and create a passcode
On some devices, you can set up Face ID or Touch ID. With these features, you can use face recognition or your fingerprint to unlock your device and make purchases. Tap Continue and follow the instructions, or tap "Set Up Later in Settings."
Next, set a six-digit passcode to help protect your data. You need a passcode to use features like Face ID, Touch ID, and Apple Pay. If you'd like a four-digit passcode, custom passcode, or no passcode, tap "Passcode Options."
Restore or transfer your information and data
If you have an iCloud backup or a backup made from your computer or an Android device, you can restore or transfer your data from your old device to your new device.
If you don't have a backup or another device, select Don't Transfer Apps & Data.
Sign in with your Apple ID
Enter your Apple ID and password, or tap "Forgot password or don't have an Apple ID?" From there, you can recover your Apple ID or password, create an Apple ID, or set it up later. If you use more than one Apple ID, tap "Use different Apple IDs for iCloud and iTunes?"
When you sign in with your Apple ID, you might be prompted for a verification code from your previous device.
Turn on automatic updates and set up other features
On the next screens, you can decide whether to share information with app developers and allow iOS to update automatically.
Set up Siri and other services
Next, you'll be asked to set up or enable services and features, like Siri. On some devices, you'll be asked to speak a few phrases so that Siri can get to know your voice.
If you signed in with your Apple ID, follow the steps to set up Apple Pay and iCloud Keychain.
Set up Screen Time and more display options
Screen Time gives you insight into how much time you and your kids spend on your devices. It also lets you set time limits for daily app use. After you set up Screen Time, you can turn on True Tone if your device supports it, and use Display Zoom to adjust the size of icons and text on your Home screen.
If you have an iPhone X or later, learn more about using gestures to navigate your device. If you have an iPhone with a Home button, you can adjust the click for your Home button.
Tap "Get Started" to begin using your device. Make a safe copy of your data by backing up, and learn about more features in the user guide for your iPhone, iPad, or iPod touch.
iPhone 13 models and iPhone 12 models work with the 5G cellular networks of certain carriers. Learn how to use 5G cellular service.
What you need
An iPhone 13 model or iPhone 12 model
A carrier that supports 5G
A 5G cellular plan1
If your new iPhone comes with a physical SIM or eSIM, use that SIM. If not, use the SIM card from your previous iPhone. In some cases, you need to contact your carrier to set up the SIM card from your previous iPhone for use with a 5G network.
Understand the 5G icons in the status bar
When you're in an area with 5G coverage for your carrier and your 5G cellular plan has been activated, you'll see a 5G icon in the status bar of your iPhone:
5G: The 5G status-bar icon.
Your carrier's 5G network is available, and your iPhone can connect to the Internet over that network.2 Not available in all areas.
5G+ and 5G UW status-bar icons.
Your carrier’s higher frequency version of 5G is available, or your iPhone has an active connection over that network. Not available in all areas.2
5G UC status-bar icon.
Your carrier’s 5G UC network is available. This can include your carrier's higher frequency version of 5G. Not available in all areas.2
Learn what to do if you don't see a 5G icon in the status bar.
Learn about 5G options
The default settings for 5G on iPhone are optimized for battery life and data usage based on your data plan. You can customize these options for when to use 5G and how much data to use in some apps.
Find these options by going to Settings > Cellular > Cellular Data Options. If you're using Dual SIM, go to Settings > Cellular and choose the number whose options you want to change.
Screenshot showing Voice & Data preferences
Voice & Data
Choose how your iPhone uses the 5G network, which can affect battery life.
5G Auto: Enables Smart Data mode. When 5G speeds don’t provide a noticeably better experience, your iPhone automatically switches to LTE, saving battery life.
5G On: Always uses 5G network when it’s available. This might reduce battery life.
LTE: Uses only LTE network, even when 5G is available.
In mainland China, you can turn on or off 5G Standalone by going to Settings > Cellular > Cellular Data Options > Voice and Data. The default setting on iPhone has 5G Standalone on with iOS 14.5 or later for mainland China. With 5G Standalone on, all cellular activity uses 5G. For more details on 5G networks, contact your carrier.
Screenshot showing Data Mode preferences
Allow More Data on 5G: Enables higher data-usage features for apps and system tasks. These include higher-quality FaceTime, high-definition content on Apple TV, Apple Music songs and videos, iOS updates over cellular, and automatic iCloud backups.
With this setting, your iPhone can automatically use 5G instead of Wi-Fi when Wi-Fi connectivity is slow or insecure on a network you visit occasionally. To turn this feature off and on for a certain network, go to Settings > Wi-Fi. Tap the info button next to the Wi-Fi network and tap Use Wi-Fi for Internet.
This setting also allows third-party apps to use more cellular data for enhanced experiences.
This is the default setting with some unlimited-data plans, depending on your carrier.
This setting uses more cellular data.
Standard: Allows automatic updates and background tasks on cellular, and uses standard quality settings for video and FaceTime. This is generally the default mode.
Low Data Mode: Helps reduce Wi-Fi and cellular-data usage by pausing automatic updates and background tasks.
Many carriers around the world support 5G roaming. If your carrier doesn't support 5G roaming, you can get cellular data through 4G or LTE networks or obtain a local SIM card or eSIM with 5G where available.
Contact your carrier for more information.
If you don't see 5G in the status bar
Make sure that you’re in an area with 5G coverage. Contact your carrier if you're not sure.
Go to Settings > Cellular > Cellular Data Options. If you see this screen, your device has 5G activated. If you don’t see this screen, contact your carrier to confirm that your plan supports 5G.
Screenshot showing Cellular Data Options
Turn on Airplane Mode, then turn it off.
If you still don't have 5G service, contact your carrier.
If you want to use 5G with Dual SIM on iPhone 12 models, make sure that you have iOS 14.5 or later.
You can choose to always stream the highest quality content by going to Settings > Music > Cellular Data and turning on High Quality Streaming and Settings > TV > Cellular and tapping High Quality. These settings use more cellular data, and content might take longer to start playing.
If you turn on Low Power Mode, 5G is disabled except in some cases like video streaming and large downloads. With iPhone 12 models, Low Power Mode disables 5G Standalone (where available).
1. Contact your carrier to check if you have a 5G plan. Some carriers might charge an activation fee.
2. Higher frequency 5G networks are supported only in the United States when using an iPhone purchased in the United
With widgets, you get timely information from your favorite apps at a glance.
With iOS 14 and later, you can use widgets on your Home Screen to keep your favorite information at your fingertips. Or you can use widgets from Today View by swiping right from the Home Screen or Lock Screen.
iPhone showing Home Screen with widgets
Add widgets to your Home Screen
From the Home Screen, touch and hold a widget or an empty area until the apps jiggle.
Tap the Add button Gray add button in the upper-left corner.
Select a widget, choose from three widget sizes, then tap Add Widget.
To add widgets from Today View:
Touch and hold a widget until the quick actions menu opens.
Tap Edit Home Screen.
Drag the widget to the right edge of the screen until it appears on the Home Screen.
iPhone showing widgets in the Today View
Add widgets to Today View
Touch and hold a widget or an empty area in Today View until the apps jiggle.
Tap the Add button gray plus icon in the upper-left corner.
Scroll down to select a widget, then choose from three widget sizes.
Tap Add Widget, then tap Done.
iPhone showing how to edit a widget
Edit your widgets
With iOS 14 and later, you can configure your widgets. For example, you can edit the Weather widget to see the forecast for your current location or a different location. Here’s how:
Touch and hold a widget to open the quick actions menu.
Tap Edit Widget Edit Widget icon.
Make your changes, then tap outside of the widget to exit.
You can also move your widgets around to put your favorites where they're easier to find. Just touch and hold a widget until it jiggles, then move the widget around on the screen.
Use widget stacks
With iOS 14 and later, you can use widget stacks to save space on your Home Screen and in Today View. You can use Smart Stacks or create your own widget stacks.
Add a Smart Stack
A Smart Stack is a pre-built collection of widgets that displays the right widget based on factors like your location, an activity, or time. A Smart Stack automatically rotates widgets to show the most relevant information throughout the day. Here's how to create a Smart Stack:
Touch and hold an area on your Home Screen or in Today View until the apps jiggle.
Tap the Add button gray plus icon in the upper-left corner.
Scroll down and tap Smart Stack.
Tap Add Widget.
iPhone showing widget stack
Create your own widget stacks
Touch and hold an app or empty area on the Home Screen or Today View until the apps jiggle.
Drag a widget on top of another widget. You can stack up to 10 widgets.
Edit a widget stack
Touch and hold the widget stack.
Tap Edit Stack. From here, you can reorder the widgets in the stack by dragging and dropping the app where you want it in the stack. You can also turn Smart Rotate* on or off. Or swipe left over a widget to delete it.
Tap the Close button gray x icon for remove when you're done.
* When Smart Rotate is on, iOS shows you relevant widgets throughout the day.
With iOS 15, you can turn on Widget Suggestions, so apps you already use can automatically appear in your Smart Stack at the right time based on your past activity. An option lets you add the widget to your stack so it’s always there when you need it. Just follow steps 1-2, then tap Widget Suggestions to turn it on.
You need iOS 14 or later to use Smart Stacks or create your own widget stacks.
Touch and hold the widget that you want to remove.
Tap Remove Widget.
Tap Remove again to confirm.