How to fix not enough disk space error on iPhone?
Sometimes the Photo app will suddenly pop up an error message stating "There is not enough disk space to continue taking photos." This Cannot Take Photo message is letting you know that the iPhone storage space is full, which must be corrected before you can take more photos or videos.
Having a full iPhone can also affect other applications on your device. To make room the dialog box suggests to "Make room by deleting existing videos or photos." You can delete photos or videos you have stored on your camera roll, or delete albums to make room. The problem is this will only free up enough space to snap an equivalent number of photos.
You can free more space by removing apps and music from your iPhone. As long as your photos, apps and music are synced to a computer or iCloud you can always put this content back on the iPhone later. Removing a few large apps or music albums will give you plenty of space for video and photo recording.