Apple iPhone XR storage is full or the device cannot install updates

The checks in more detail

Years of photos, videos, messages and apps accumulate on it, and iOS needs several gigabytes free to update and to work well. Open Settings, General, iPhone Storage. The bar shows what uses the space, with categories for apps, photos, system data and others, and the list below shows each app with its size and the date last used. Start with the biggest items. Photos and videos are usually the largest: turn on iCloud Photos with Optimize iPhone Storage in Settings, Photos, which keeps full-resolution images in iCloud and smaller versions on the phone;

or copy them to a computer and delete them from the phone. Check the Recently Deleted album, which holds photos for 30 days, and empty it. Review videos, which take the most space, and delete screen recordings and old clips. Then apps and messages. In iPhone Storage, tap an app to Offload App, which removes the app but keeps its data, or Delete App for ones you do not use; the phone offers to offload unused apps automatically. In Messages, review large attachments and set messages to be kept for a year rather than forever.

Clear Safari's history and website data in Settings, Safari, and check Podcasts, Music and Files for downloads. If System Data is huge, restart the phone, which clears caches. Do not forget that a backup to iCloud or a computer lets you delete freely. If storage remains tight after these steps, an iCloud storage plan or an external drive is the lasting answer. Update iOS only when you have the space. Quote the serial number to Apple if the storage figure looks wrong.