There is a button called "free up space" it should say "free up space on your phone" and explain what is about to happen. If you press it, all of the photos and videos on your phone are deleted and uploaded to the cloud. Great until you realise they're all at a low resolution. My videos are now useless. Thanks Google. I've lost hours and hours of footage for a project. Furthermore it dissolved the folders that I'd spent hours arranging.