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When you buy your iPhone, iPad, or iPod touch, it comes with a set storage capacity ranging from 16 to 512 GB for iPhone, 16 GB to 1 TB for iPad and 8 to 256 GB for iPod touch. The music you buy, the apps you download, the photos you take, and all of the other content that you enjoy on your device uses its storage. And depending on the size of your capacity and how much content you have, your device can fill up and run out of storage. When your device is full, you can’t increase its storage. But you can free up space.
See how much storage you have
Go to Settings.
Tap [device] Storage.
You might see a list of recommendations for optimizing your device storage, followed by a list of installed apps and the amount of storage each one uses. Tap an app's name for more information about its storage.
If you're using iOS 10 or earlier, below Storage, tap Manage Storage to see which apps take up the most space.
Free up space on your device
You can make storage space available on your iPhone, iPad, or iPod touch when you use iCloud Photos and turn on Optimise Storage. Or you can remove content from your apps – like photos, music, and podcasts – or delete the apps that you're not using.