Why won't my iPhone 5 take pictures?

My iPhone won't let me take pictures, save pictures, or screenshot. I tried deleting pictures and I deleted over 800. I now know storage is not the problem. Each time I try to save a photo (usually from twitter) an error message pops up saying "Error; Write Busy". At first I thought it was a twitter glitch but then I realized I could not take pictures through the iPhone camera app, or any other outsider camera application.

Try to restore it. If these don't work, bring your phone into Apple for replacement.