Being Tricky
The short answer
iPhone storage full? Go to Settings → General → iPhone Storage to see what's using space.
At a glance
About 15 minutes · Medium · For iPhone
Key point 1 of 5
Your iPhone has a fixed amount of built-in storage, such as 128 GB or 256 GB.
Key point 2 of 5
Apple groups your storage into categories:
Key point 3 of 5
By default, every photo and video on your iPhone is stored at full resolution, which takes a lot of space.
Key point 4 of 5
Apple says the Other or System Data section includes items you can't remove, such as Siri voices, fonts and dictionaries, plus system logs and caches.
Key point 5 of 5
Apple says that when storage is low, the iPhone automatically removes items it can download again, like cached files.
Watch out
With iCloud Photos on, deleting a photo on your iPhone deletes it on all your devices.
You might ask
How do I free up iPhone storage without deleting photos?
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Being Tricky