Why “Other” storage is large on iPhone, and what you can safely clear
You open Settings, General, iPhone Storage, and a grey section is eating a big part of the bar. Older versions of iOS called it Other. Newer versions call it System Data. Either way, it is the part you cannot tap into, and it is the one people most often want to shrink. This guide explains what is in it and which actions help. It also says what no app can do, because that is where many “cleaner” promises fall apart.
What the label means
iPhone Storage splits your space into groups: Apps, Photos, Media, Messages and so on. Whatever iOS cannot assign to a clear group lands in System Data (or Other). It is a catch-all, not one folder.
It typically includes:
- The operating system files and the room iOS needs to run and update.
- Caches, which are temporary copies that apps and the system keep to work faster.
- Logs and diagnostic files.
- Fonts, voices for Siri, dictionaries and language data you downloaded.
- Parts of streamed or downloaded content that apps keep as temporary data.
- Leftovers from software updates.
Most of this is normal. A system that has been running for a while carries more caches than a fresh one. The number can also jump after an iOS update or after you have streamed a lot of video.
Why it can get so large
A few patterns cause the biggest numbers:
- Heavy streaming. Video and music apps cache what they play.
- Large Safari data, particularly if you use websites that store a lot.
- Apps that never clean up their own temporary files.
The figure also changes with the moment. Right after a restart or an update, iOS may take a while to calculate, and it may show an old number until it catches up.
What you can safely do
You cannot delete System Data directly, and this is true on every iPhone. These steps are safe and sometimes help:
- Restart the iPhone. It clears some temporary files, and it is free.
- Install pending iOS updates. Updates tend to tidy leftovers, though you need room to install them.
- Clear Safari history and website data. In Settings, Safari (in iOS 18, Settings, Apps, Safari), choose Clear History and Website Data. You will be signed out of some websites, so have your passwords in reach.
- Review streaming and downloads. Music, podcasts and video apps often have a setting that shows and removes downloaded content.
- Offload or reinstall a heavy app. If an app shows a large size in iPhone Storage far beyond its normal footprint, deleting it and installing it again can drop its cache. Make sure you do not lose data that lives only inside it.
- Shorten how long Messages are kept. Settings, Messages, Keep Messages lets you keep conversations for 30 days or a year. This removes older messages, so think before you change it.
Do these one at a time and check iPhone Storage after each. That way you learn which one mattered.
What not to do
Be wary of any tool that claims to clean System Data. On iPhone, apps run in sandboxes. They can reach their own files and the data you give them access to, such as photos. They cannot enter the system’s caches or other apps’ storage. Anything that promises otherwise either does not work or does something else.
Also avoid erasing the phone just to shrink one grey bar. If you ever decide to do that, make a full backup first, and be aware that you will need time to restore. For most people it is not worth it.
What Poofora does and does not do
We want to be clear here, because the title of this page is the sort of thing that tempts a lot of apps to exaggerate.
Poofora does not clean System Data, caches or other apps. It works with your photo library and your contacts. It finds duplicate and similar photos, screenshots and big videos, and it finds duplicate contacts. Everything is analyzed on your iPhone, and you review everything before anything is deleted.
Why mention it in a guide about System Data? Because photos and videos are usually the biggest part of iPhone Storage that you control. If you look at the bar and Photos is large, that is where the real room is. And Poofora has its own small amount of data on the iPhone, a scan cache, which you can clear in Poofora Settings with Clear scan cache.
Photos deleted but space not back
A common reason people think System Data is the culprit is that they deleted a lot of photos and saw nothing change. The reason is usually Recently Deleted. iOS keeps deleted photos there for up to 30 days, and the space returns when they leave. Open Photos, Albums, Recently Deleted to check. See what happens to deleted photos and iCloud for details.
A realistic way to think about it
System Data will never be zero, and it will go up and down. Treat it as a number to keep an eye on rather than a target. If it has grown to a size that is hurting, the restart, update and Safari steps above are the safest first moves. If you need real space, work on the part you control: photos, videos, apps and Messages. How to free up storage on iPhone gives an order that works.
Poofora is coming soon to the App Store. You can read what it does on the home page.