My IPhone 5s camera isn't turning on, the screen is black for every app I use for the camera and none of them work. I've turned my phone off and on again and that didn't work and I also tried resettingy phone. Any suggestions on how to fix it?

if the camera stays black when trying to use it in any application it is likely a hardware issue at that point because the aperture on the camera isn't opening. the only way to is that is by actually having the iPhone repaired through an apple store or through contacting apple support and going through a mail in repair.

if the iPhone is out of warranty though there would be a cost to have it repaired and it may end up being cheaper to take it to a third party to have them repair or replace just the camera.

I have had the same issue. It started with camera not working at all. 3-4 days later my front camera started working, all by itself. The rear camera has worked 2-3 times so far. It works specially when I connect the phone to my laptop for charging!