How to free up storage on your phone
Storage warnings almost never mean your photos are the problem. Reading the breakdown properly tells you which category is actually growing, and which of the popular tricks reclaim nothing at all.
Reading the storage breakdown
On iPhone and iPad, open Settings > General > iPhone Storage. A coloured bar splits usage into apps, media, photos, mail and system, and below it sits a list of apps sorted by size, each showing app size separately from documents and data.
Android puts the same view in Settings > Storage on Pixel and stock builds; Samsung tucks it inside Battery and device care. Tap any category to drill into the files behind it. Wording moves between versions, which the Android settings hub tracks release by release.
Sort by size before you delete anything. One video app holding several gigabytes of cached downloads is far more common than a thousand oversized photos, and the free up storage guide shows both screens in detail.
What System and Other really are
iOS labels this System Data, previously Other. It is a bucket for caches, logs, streamed video and music left on disk, Siri voices, keyboard dictionaries and update files, and it grows and shrinks on its own.
Android's equivalent System entry covers the operating system image, its updates and internal working files. Neither can be deleted directly, and no setting exposes a clean button for them, however deep you dig.
If System Data has ballooned to many gigabytes, the usual causes are an interrupted update or a heavily used streaming app. Restarting clears part of it, installing the pending update clears more, as the software update guide explains.
Offloading versus deleting apps
iOS offers two very different actions on each app's page, and the difference matters.
| Offload App | Removes the app binary, keeps documents and data, icon stays with a cloud badge, reinstalling restores your data |
| Delete App | Removes the app and all of its local data permanently |
Offloading is the safer first move for large games and apps you use occasionally. There is also an automatic option that offloads unused apps for you when space runs short.
Android has no direct equivalent, but uninstalling an app whose content lives in the cloud has a similar effect, and the iOS versus Android comparison covers where the two diverge.
Clearing caches without losing data
On Android, open an app's info page and look for Storage and cache. Clear cache is safe: it drops temporary files that rebuild themselves. Clear storage is not: it resets the app to a fresh install and signs you out.
iOS gives no per-app cache button. Instead, use each app's own settings, for example clearing downloaded episodes in a podcast app, or delete and reinstall the app to reset its cache.
Also empty the deleted items album in Photos. Removed pictures sit there for around 30 days and keep occupying space until the album is emptied, so a big photo purge frees nothing until you do.
Cleanups that do not help
Closing background apps frees memory, not storage, and changes the storage bar not at all. Third-party cleaner apps mostly delete caches the system would have cleared anyway, while occupying space themselves.
Turning off cloud photo sync does not shrink anything either. The opposite setting, which keeps smaller optimised copies on the device, is the one that actually saves space.
A factory reset does free the drive, but it is a last resort rather than maintenance, as the reset guide makes clear. You can also search any storage screen by name from the storage settings finder. To explore the menus safely, open the storage screens in the settings simulator and click through them on any system before touching your own device.
Try it yourself, on the real menusOpen any of 43 operating systems in your browser and walk the Settings tree exactly as it appears on the device. No download, no account.Frequently asked questions
Why is System Data so large on my iPhone?
It collects caches, logs and streamed media left on disk. It usually shrinks on its own after a restart or once a pending update installs, and it cannot be deleted manually.
Is clearing an app's cache safe?
Yes on Android, where Clear cache only removes temporary files. Avoid Clear storage, which wipes the app's data and signs you out as if it were freshly installed.
Does offloading an app keep my data?
Yes. Offloading removes only the app itself and keeps its documents and data, so reinstalling from the greyed-out icon restores everything where you left it.