How Much Storage Do Built-In Apps Use on iPhone?

When the “Storage Almost Full” alert appears, it is natural to suspect Apple’s own apps, since you never chose to install most of them. To find out, open Settings, tap General, then tap iPhone Storage. That screen lists every app, built-in ones included, with the space each uses. This guide, written for current versions of iOS, explains how to read those numbers, which Apple apps you can offload or delete, and what the iOS and System Data lines mean.

iMovie isn’t one of these built-in apps, but if it sits near the top of your storage list, here is how to delete iMovie and get that space back.

Why there is no single answer for Apple’s apps

People often look for a fixed figure, such as “built-in apps take 5 GB.” No such number exists, because each built-in app has two parts that grow at very different rates:

• The app itself. This is the program code Apple ships. For most built-in apps it is modest and changes only when iOS updates the app.
• The content the app holds. This is everything you add: photos and videos in Photos, conversations and attachments in Messages, downloaded mail in Mail, offline maps, downloaded songs in Music, voice recordings in Voice Memos, and so on. This part can be close to zero on one iPhone and many gigabytes on another.

The only reliable figure is the one your own iPhone reports in Settings.

It also helps to separate built-in apps from the operating system. iOS itself, and the system files that support it, are not counted as apps at all. They appear as their own lines in the storage list, which is covered further down. When an old guide says “pre-installed apps take a couple of gigabytes,” it is usually mixing the two together.

A related point explains why a new iPhone never shows its full advertised capacity as free. Part of the space is taken by the operating system before you install anything, and Apple notes that the space used by the system varies based on your device and model. Apple’s page on how storage capacity is measured explains that advertised capacity uses decimal units (1 GB = 1 billion bytes) and that actual formatted capacity is less.

Read each built-in app’s size in Settings

Follow these steps on the iPhone.

1. Open the Settings app from your Home Screen or App Library.
   

   

2. Tap General.
   

   

3. Tap iPhone Storage. Apple’s documentation describes this row as “[device] Storage,” so on an iPhone it reads iPhone Storage.
4. Look at the bar at the top. It shows used space against total capacity, split into colored categories such as Apps, Photos, Messages and System.
5. Scroll past any recommendations to the list of apps. Third-party apps and Apple’s apps appear together in the same list, each with its total size on the right. Built-in apps are easy to spot by name: Photos, Messages, Mail, Music, Podcasts, Books, Maps, Voice Memos, Notes and so on.
   

   

6. Tap the name of any built-in app to open its detail screen and see how that total breaks down.

A few built-in apps may not appear in the list at all. That usually means they hold very little, or that their content is counted elsewhere: for example, iPhone Storage gives Photos and Messages their own categories in the bar. Apple also notes that cached data and temporary data might not count as usage, so a total can drop on its own after iOS clears caches.

If you want a wider tour of the storage screen, including the recommendations and the categories in the bar, see how to check your iPhone storage. The rest of this guide stays with Apple’s own apps.

What the detail screen tells you

The detail screen for a built-in app answers the question this guide started with. Apple describes it simply as more information about the app’s storage, plus the choice to offload the app or delete it. Many iPhones split the total into two figures, often labeled App Size and Documents & Data. Apple’s page doesn’t name them, so the wording on your screen may differ.

The app versus its content

• App Size is the space the app’s program files take. For a built-in app, this is the part Apple controls.
• Documents & Data is the space taken by what the app stores for you: cached files, downloads, attachments, recordings and settings.

If App Size is small and Documents & Data is large, deleting the app is not the main fix. The space belongs to your content, and you can usually reclaim it inside the app without removing it (see the trimming section below). If App Size is the larger number and you never use the app, removing it is a reasonable choice.

Apple adds that, depending on the app, you might be able to delete some of its documents and data from this screen.

Offload versus delete

Apple gives you two ways to remove an app from this screen, and they behave very differently:

Option	What is removed	What stays	Good for
Offload the app	The app’s program files	Its documents and data	An app with a large App Size you use only now and then
Delete the app	The app and its related data	Nothing from that app on the iPhone (data synced to iCloud may still exist there)	An app you don’t use and whose content you don’t need

Offloading frees only the App Size part. For many built-in apps that is a small amount, so offloading Apple’s apps rarely solves a full-storage warning. When you reinstall an offloaded app, its data is still there. The same idea applies to third-party apps, which is covered in deleting an app but keeping its data.

Built-in apps that aren’t on Apple’s removable list (see below) can’t be deleted from this screen either.

Where Photos, Messages, Mail and Safari keep their space

On most iPhones, a handful of Apple apps hold most of the built-in storage. Knowing what each one stores tells you where to look first.

Built-in app	What usually takes the space	Can it be deleted?
Photos	Photos and videos, especially 4K video, plus items in Recently Deleted	Not on Apple’s standard list (EU exception below)
Messages	Photos, videos, voice messages and other attachments in conversations	Not on Apple’s standard list (EU exception below)
Mail	Downloaded messages and attachments for each account	Yes
Safari	Website data, offline Reading List items and caches	Not on Apple’s standard list (EU and Japan exceptions below)
Music, Podcasts, TV, Books	Downloaded songs, episodes, videos and books	Yes
Voice Memos, Notes	Recordings, and notes with images, scans or attachments	Yes
Maps	Downloaded offline maps	Yes

If Photos dominates, the most effective long-term fix is usually iCloud Photos with optimized storage, which keeps smaller versions on the phone. That setup is explained in how to optimize iPhone storage for photos. If Messages is the large one, viewing Messages storage shows how to find the biggest conversations.

Trim a built-in app without removing it

These are the places to start. On current versions of iOS, an app’s settings are under Settings > Apps > the app name; on older iOS versions the app is listed directly in Settings.

Photos

1. Delete photos and videos you don’t need, starting with long videos.
2. Open the Recently Deleted collection (below Utilities). Apple keeps deleted photos and videos there for 30 days, and they still use space until that period ends or you empty the collection.

Emptying Recently Deleted is permanent for those items on this iPhone, so check the collection before you clear it.

Messages

1. To find large attachments in one conversation, open it, tap the contact or group icon at the top of the conversation, then tap a category such as Photos and delete what you don’t need.
2. To stop old conversations from piling up, go to Settings > Apps > Messages, scroll down and tap Keep Messages (below Message History). Choose 30 days or a year instead of Forever.
3. Deleted messages and attachments go to the Recently Deleted folder in Messages and stay there for 30 days, per Apple’s Messages guide.

Changing Keep Messages removes older conversations and their attachments from the iPhone. If you use Messages in iCloud, your other devices may be affected too, so decide before you change it.

Safari

Go to Settings > Apps > Safari, scroll down and tap Clear History and Website Data, as described on Apple’s Safari page. This removes browsing history, cookies and website data, so you will be signed out of many websites.

Mail, Music and other media apps

• Mail: Delete old messages with large attachments, and empty the Trash folder for each account.
• Music, Podcasts, TV and Books: Remove downloads you have already listened to or watched. The items stay in your library and can be downloaded again.
• Voice Memos and Notes: Long recordings and notes with scans add up. Delete what you no longer need; deleted items can stay in a Recently Deleted folder until you empty it.
• Maps: Delete offline maps for areas you no longer travel to.

Let iOS offload apps you stop using

If you’d rather not manage this by hand, go to Settings > Apps > App Store and turn on Offload Unused Apps. Apple’s App Store settings page describes it as automatically removing unused apps, with the option to reinstall an app at any time if it’s still available in the App Store. Data is kept, as with a manual offload. The feature is explained further in how to automatically offload unused apps.

Apple apps you can delete

Apple’s support article on deleting built-in apps says that with iOS 14 or later you can delete some built-in Apple apps. Its list for iPhone is:

Activity, Apple Books, Apple TV, Calculator, Calendar, Clock, Compass, Contacts, FaceTime, Files, Find My, Freeform, Health, Home, iTunes Store, Mail, Maps, Measure, Music, News (where available), Notes, Podcasts, Reminders, Shortcuts, Stocks, Tips, Translate, TV (where available), Voice Memos, Wallet, Watch app and Weather.

Apps such as Safari, Messages, Photos, Camera, Phone, Settings and the App Store are not on that list. In the European Union, Apple’s page on default apps in the EU says you can also delete Messages, the App Store, Camera, Photos and Safari, and in Japan you can delete Safari. Before deleting Messages, the App Store or Safari, you first need to install an alternative app and set it as the default.

How to delete a built-in app

1. On the Home Screen, touch and hold the app.
2. Tap Remove App or Delete App from the shortcut menu.
3. Tap Delete App or Delete to confirm.

You can also delete the app from its detail screen in iPhone Storage. The general method, including deleting from the App Library, is the same as for any app and is covered in how to delete apps on iPhone. GarageBand is a common example: it is an Apple app from the App Store rather than one of the built-in apps listed above, so it deletes like any other app, and deleting GarageBand without losing your songs walks through saving projects first.

What changes when a built-in app is gone

Apple warns that deleting a built-in app also deletes any related user data and configuration files, and some features elsewhere change too. According to Apple’s article:

• Deleting Podcasts, Apple Books, Maps or Music removes them from CarPlay.
• Deleting Calculator removes the calculator from Control Center.
• Deleting Stocks or Weather removes that information elsewhere, such as in Notification Center.
• Deleting Contacts keeps your contact information in the Phone app.
• After deleting FaceTime, you can still make and receive calls through Contacts and the Phone app.
• Deleting Health or the Watch app from an iPhone paired with an Apple Watch requires unpairing the watch first.
• Deleting an app from a paired iPhone also removes it from the Apple Watch.

Before you delete an app such as Notes, Voice Memos or Mail, check whether its content is synced to iCloud or another account. Content stored only on the iPhone goes with the app.

Bring back a built-in app

You can restore a deleted built-in app from the App Store:

1. Open the App Store.
2. Search for the app using its exact name, such as “Calculator” or “Voice Memos.”
3. Tap the Redownload button and wait for the app to finish restoring, then open it from your Home Screen.

Restoring the app also brings back features that depended on it, such as Calculator in Control Center. If you see a cloud icon in the App Store next to the app, it simply means you can download it again; why there is a cloud next to an app explains that icon.

The iOS and System Data lines are not apps

At the bottom of the app list in iPhone Storage you will usually see entries for the operating system rather than for any app. Apple’s storage article calls this System; on many current iPhones the list shows it as lines such as iOS and System Data.

• iOS (System): Apple describes it as space taken by the operating system, which can vary based on your device and model. You can’t delete it.
• System Data: files, caches and temporary data the iPhone manages. Apple says the device removes cached and temporary files when it needs space, so you don’t have to.

Neither line belongs to a built-in app, so deleting Apple’s apps won’t reduce them, and Apple doesn’t document a way to clear System Data by hand.

A worked example: a full 128 GB iPhone

Here is how the steps fit together on a hypothetical phone. The figures are fictional and only illustrate the method.

A student gets the “Storage Almost Full” alert on a 128 GB iPhone and opens Settings > General > iPhone Storage. The list shows:

Item	Total	What the detail screen shows
Photos	48 GB	Recently Deleted holds 6 GB
Messages	14 GB	Several group chats with years of videos
GarageBand	1.8 GB	Mostly App Size, never opened
Podcasts	3 GB	Mostly downloaded episodes
Calculator	A few MB	Almost all App Size

Deleting Calculator would save almost nothing. The effective moves are emptying Recently Deleted in Photos (6 GB), removing videos from the largest group chats and setting Keep Messages to a year, removing played Podcasts episodes, and deleting GarageBand, which is unused. Together these clear more than 10 GB without losing anything the student wants, and every Apple app removed can be redownloaded later.

On iOS 10 and other older versions

Older guides, and older iPhones, use different labels. On iOS 10 the path was Settings > General > Storage & iCloud Usage, then Manage Storage under the Storage section, which opened the same kind of per-app list.

iOS 10 was already the first version that let you remove many built-in apps, such as Calculator, Stocks, Tips and Voice Memos, from the Home Screen. Apple’s current list applies to iOS 14 or later. If your iPhone can’t update past an older version, you can still read the per-app list and trim content inside each app, which is where most of the space is anyway.

Built-in app storage questions

Will deleting Notes or Voice Memos delete my notes and recordings?

Content stored only on the iPhone is deleted along with the app. Content synced through iCloud stays in iCloud and returns when you redownload the app and sign in with the same Apple Account, so check your sync settings first.

Can I delete Messages or Photos to save space?

Only in the European Union, where Apple allows those apps to be deleted. Elsewhere, reduce their size by deleting attachments, photos and videos, emptying Recently Deleted and, for Photos, turning on optimized storage with iCloud Photos.

Once you know which Apple apps are worth trimming, the remaining space usually comes from your own photos and third-party apps. For more places to look, see ways to free up iPhone storage, and if you are unsure whether a full warning is about the phone or your iCloud plan, read iPhone storage vs. iCloud storage.