Applications are the apps you installed, plus the data they store on your phone
When you open Settings, tap General, then tap iPhone Storage, you see a list of apps with numbers next to them. That number is the Applications category — it shows how much space each app takes up, including the app itself and all the files it has saved on your phone.
An app like Instagram, for example, might show 500 MB. That includes the Instagram program code (maybe 100 MB) plus all your downloaded photos, videos, cached stories, and login information stored on your phone (the other 400 MB). When you delete an app, all of that disappears.
This is different from the other storage categories you see on that same screen — Documents & Data, Photos & Videos, Mail, and so on. Those are files that don't belong to any single app. Applications are always tied to a specific app you installed.
Key Takeaways
- The Applications category in iPhone Storage shows both the app itself and everything it has saved — photos, cache, login data, and settings.
- Each app's number includes its program code plus all the files it has stored, so a large number usually means the app has been saving a lot of data.
- Deleting an app removes both the program and all its stored data from your phone at once.
- You can see which apps are taking the most space by sorting the list in Settings, which helps you decide what to delete if you need more room.
Why some apps take up much more space than others
Apps that work with photos, videos, or music tend to have large numbers because they store those files locally on your phone. Spotify might show 2 GB if you have downloaded playlists for offline listening. TikTok might show 1.5 GB if you have watched a lot of videos — the app caches them so they play smoothly the next time you open it.
Apps that only show text and connect to the internet — like Twitter or Gmail — usually stay small because they don't save much on your phone. They fetch new information from their servers each time you open them.
Some apps also grow over time. Messaging apps like WhatsApp or iMessage store every photo, video, and file you have ever sent or received. If you have been using the app for years, that number can climb to several gigabytes.
How to see what's taking up space inside an app
Tap any app in the iPhone Storage list to see a breakdown. You will see the app size itself, plus a section called "Documents & Data" that shows everything the app has saved. For Instagram, this might show 200 MB of cached images and 50 MB of your profile data.
Not every app shows this breakdown clearly — some just show a single number. But the ones that do let you understand whether the app itself is large (meaning it has a lot of features) or whether it is the stored data that is taking up room.
If an app is taking up too much space and you want to keep using it, you can sometimes clear its cache without deleting the app. Go to Settings, tap General, tap iPhone Storage, tap the app, then tap "Offload App." This removes the program but keeps your data. When you reinstall it, your login and settings stay the same.
The difference between Applications and other storage categories
Your iPhone divides storage into categories to help you understand where your space is going. Applications is one of them — it only counts apps you installed and their data. The other categories are:
- Photos & Videos: Pictures and videos in your Camera Roll and photo library, not including photos stored inside apps.
- Mail: Emails you have downloaded, including attachments.
- Documents & Data: Files saved by apps that don't fit neatly into other categories — like PDFs in your Notes app or documents in cloud storage apps.
- System Data: The iOS operating system itself, plus things like Siri voice data and system caches.
A photo you take in the Camera app counts toward Photos & Videos. The same photo saved inside Instagram counts toward Applications because it is stored by the Instagram app. If you send that photo in an email, it also counts toward Mail. The same file can appear in multiple categories because it is stored in multiple places on your phone.
When to delete apps to free up space
If your iPhone storage is nearly full, look at the Applications list and delete the apps you don't use regularly. Sorting by size (tap Edit at the top of the list) shows you which apps are taking the most room. If an app shows 1 GB or more and you have not opened it in weeks, deleting it is usually safe.
Before you delete an app that stores important data — like a banking app, a notes app, or a messaging app — make sure that data is backed up somewhere else. Most apps sync to the cloud automatically, but not all of them. Check the app's settings first.
If you delete an app and later want it back, you can reinstall it from the App Store for free. Your login information and settings may or may not come back depending on whether the app syncs to the cloud — this varies by app.
How app updates affect the Applications number
When you update an app, the Applications number might go up or down. A new version of the app might include more features (taking more space) or might be optimized to run more efficiently (taking less space). You cannot control this — it depends on what the app developer changed.
Updates also sometimes clear out old cached data, which can make the number shrink. If an app has been storing old files it no longer needs, an update might clean that up automatically.
The Applications number you see in Settings is usually updated within a few hours of installing or updating an app, but sometimes it takes longer. If the number seems wrong, restart your iPhone and check again.
Frequently Asked Questions
Can I see what files an app has stored without deleting it?
Not always. Some apps show a breakdown in Settings under iPhone Storage, but most do not. You can see the total size, but not the individual files inside. If you want to know exactly what an app is storing, your best option is to look inside the app itself — many apps have a Settings or Storage section that shows cached data or downloaded files.
If I delete an app, will I lose my login information?
Usually yes, unless the app syncs to the cloud. When you delete an app, all its stored data goes with it. When you reinstall it, you will need to log in again. Some apps like Gmail or Outlook sync your login to their servers, so you can log back in when ready. Others do not, so you will need your password.
Why does an app show a large size even though I don't use it much?
The app is probably caching files — storing copies of things you have viewed so they load faster next time. Social media apps and video apps do this constantly. You can sometimes clear this cache by offloading the app (which removes it but keeps your data) and then reinstalling it.
Does the Applications number include photos I took in the Camera app?
No. Photos you take with the Camera app show up under Photos & Videos, not Applications. The only photos that count toward Applications are ones stored inside other apps — like photos you downloaded in Instagram or saved in a messaging app.
What happens to the Applications number if I turn off iCloud sync for an app?
The number stays the same. Turning off iCloud sync only affects whether the app backs up to the cloud — it does not change how much space the app takes on your phone. The app still stores everything locally on your device.