Redditor aoisenshi shared this tip for navigating your home if you're nearsighted and stuck without glasses. If you can spot your phone, open up the camera app (you can do it from the lock screen on iPhone) and use the open "viewfinder" to see around you in sharp focus.
It works because cameras always have perfect vision, so your phone will display a crisp image on screen of whatever is in front of you. You can then hold your phone nearer to your eyes at whatever focal length is best to get an in-focus image of anything in your house.
This tip could come in handy if you need to search around for your spectacles, or if you just want to make it from the bed to the bathroom without tripping on a shoe.