What is "System" or "Other" storage on Android?

What is inside System storage?

• The Android operating system and pre-installed apps.
• Space reserved for seamless updates on phones that keep two copies of system partitions.
• Temporary files used while installing an update, which shrink after a restart.
• On some phones, a reserve so the device keeps working when storage is nearly full.

On a 128 GB phone, System commonly shows 15 to 30 GB depending on brand and Android version. It is also why a phone sold as 128 GB never shows 128 GB free: the marketed capacity counts all of it, and storage makers use 1 GB = 1,000,000,000 bytes while phones may display binary units.

Brands differ. Samsung adds its own apps and services to the system image, Pixel keeps a leaner set, and some phones count the space for pre-loaded apps under Apps rather than System, which makes comparisons between phones misleading.

What is inside Other storage?

Photos saved by chat apps usually count under Images, not Other. If Images is the large slice, the clutter is in folders such as WhatsApp's; see the WhatsApp media folder page.

Other can also include files saved by apps into shared folders with unusual extensions, such as backups, logs or exported chats. A file manager that sorts by size is the quickest way to spot them, and anything you recognise as old can go.

Phones from different brands label this group as Other files, Miscellaneous or Documents and other. The name does not change what is inside.

How can you shrink what you can control?

1. Restart the phone. Leftover update files are often cleared on reboot.
2. Install pending system updates; a half-finished update holds extra space.
3. Clear caches of the biggest apps, not storage. See app cache for the difference.
4. Sort internal storage by size in a file manager and remove old downloads and abandoned app folders.
5. Check Images and Videos last; they are usually the largest category of all.

Moving apps or media to an SD card, where the phone allows it, frees internal space without touching System. The adoptable storage page covers the two ways Android can use a card, and why one of them ties the card to a single phone. Factory resetting a phone also shrinks Other, but it erases everything, so treat it as a last resort after a full backup.