Why your iPhone slows down when apps take up too much space
Apps accumulate data over time — cached images, login information, temporary files from updates, and old versions of content you've already seen. When your iPhone storage fills up, the phone has less room to create the temporary files it needs to run smoothly, which makes everything slower. Clearing app data doesn't delete the app itself; it removes the junk that builds up inside it.
You have three ways to do this, depending on how much you want to keep. You can clear data from individual apps without uninstalling them, offload an app (which removes it but keeps your data), or delete the app entirely and reinstall it fresh. Which one you choose depends on whether you want to keep your login information and settings.
Key Takeaways
- Clearing an app's cache and data removes temporary files and old content without deleting the app itself, and you stay logged in.
- Go to Settings > General > iPhone Storage, find the app you want to clear, and tap "Offload App" to remove it while keeping your data, or "Delete App" to remove everything.
- Offloading takes up almost no space but keeps your login information; deleting and reinstalling clears everything but takes longer to set back up.
- Apps like Photos, Mail, and Maps often hold the most cached data, so clearing those first usually frees up the most space.
- Check your iPhone Storage list regularly to see which apps are using the most space and which ones you haven't opened in months.
How to offload an app without losing your login information
Offloading removes the app from your phone but keeps your data, settings, and login information stored on iCloud. When you reinstall it later, everything comes back exactly as you left it. This is the safest option if you want to free up space without starting from scratch.
Open Settings, tap General, then tap iPhone Storage. Scroll through the list and find the app you want to clear. Tap the app name, then tap "Offload App." A warning will appear asking you to confirm — tap "Offload App" again. The app disappears from your home screen and storage space is freed when ready. To bring it back, open the App Store, search for the app by name, and tap the cloud icon with a read arrow. It reinstalls in a few seconds with all your data intact.
Offloading works best for apps you use occasionally but not every day — things like banking apps, travel apps, or games you play in bursts. It takes almost no storage space to keep your data on iCloud, so you can offload multiple apps without worry.
How to delete an app and start fresh
Deleting an app removes everything — the app itself, all your data, your login information, cached files, and settings. Use this when you want a completely clean slate or when an app is malfunctioning and you want to rule out corrupted data as the cause.
Go to Settings > General > iPhone Storage, find the app, and tap "Delete App." Confirm by tapping "Delete App" again. The entire app vanishes. To use it again, go to the App Store and read it fresh. When you open it, you'll be logged out and back at the first-run setup screen. You'll need to log in again and reconfigure any settings you had.
This method frees up the most space because nothing is kept on iCloud. The downside is that you lose all your saved data — game progress, email drafts, saved searches, or any other information the app stored. Only delete an app completely if you're certain you don't need that data back.
Which apps usually hold the most cached data
Photos and Camera are often the largest offenders because they store thumbnail previews and edited versions of images. Mail caches every email you've downloaded, plus attachments. Maps stores offline maps and search history. Social media apps like Instagram, TikTok, and Facebook cache videos and images so they load faster when you scroll.
Open Settings > General > iPhone Storage and look at the numbers next to each app. Anything over 500 MB is worth checking. Tap the app name to see a breakdown — "Documents & Data" is usually the cached stuff you can safely clear by offloading or deleting. "App" is the app itself, which you can't remove without deleting the whole thing.
Streaming apps like Netflix, Spotify, and YouTube also cache downloaded content. If you've downloaded episodes or playlists for offline use, those take up real space. You can delete individual downloads within the app itself without clearing the whole app — open the app, find your downloads, and delete the ones you've already watched or heard.
How to clear cache without removing the app
Some apps let you clear their cache from within the app's own settings, which is faster than offloading. Open the app, look for Settings or Preferences (usually a gear icon), and search for options like "Clear Cache," "Clear Data," or "Storage." Not every app has this option — it depends on how the developer built it.
If the app doesn't have a built-in clear option, your only choices are offload or delete. This is why offloading is useful: it clears the cache without making you log back in, and it's faster than uninstalling and reinstalling.
What happens to your data when you offload versus delete
| Action | App Removed | Data Saved | Login Info Kept | Space Freed |
|---|---|---|---|---|
| Offload App | Yes | Yes (on iCloud) | Yes | Almost all |
| Delete App | Yes | No | No | All |
| Clear Cache (in-app) | No | Yes | Yes | Some |
How to check which apps you haven't used in a while
iPhone Storage shows you when you last opened each app. Go to Settings > General > iPhone Storage and look for the date next to each app name. If an app says "Last opened 3 months ago" or longer, it's a candidate for offloading. You're freeing up space from something you're not actually using.
Scroll through the entire list and make a mental note of apps you forgot you had. Many people have old games, trial versions of apps, or one-time-use tools sitting on their phone taking up space. Offload anything you haven't touched in six months — if you need it again, it's one tap away in the App Store.
Frequently Asked Questions
Will I lose my photos if I offload the Photos app?
No. Your photos are stored in iCloud Photos (if you have it turned on) or in your phone's main storage, not inside the Photos app itself. Offloading the Photos app only removes the app and its cached thumbnails. Your actual photos stay safe. When you reinstall the app, your photos reappear.
Can I offload multiple apps at once or do I have to do them one by one?
You have to offload them one at a time through Settings. There's no bulk offload option. However, it only takes a few seconds per app, so clearing five or six apps takes less than a minute total.
What's the difference between offloading and deleting if I'm just going to reinstall the app anyway?
Offloading keeps your data on iCloud, so when you reinstall, you're logged in and everything is exactly as you left it. Deleting removes everything, so you have to log back in and reconfigure settings. If you plan to use the app again soon, offload. If you're done with it or it's broken, delete.
Why does my iPhone still feel slow after I clear apps?
App data is usually not the main cause of slowness — a full storage drive is. If your iPhone Storage shows you're using 90% or more of your total space, the phone can't create temporary files it needs to run. You may need to delete photos, videos, or larger apps, not just clear cache. Check Settings > General > iPhone Storage to see what's taking up the most room overall.
Do I need to clear app data regularly or just when I'm running out of space?
Only when you need the space. Clearing app data doesn't improve performance unless your storage is nearly full. If you have plenty of free space, there's no benefit to offloading or deleting apps. Just do it when iPhone Storage shows you're above 85% capacity.