There are three options on the market right now that till allow you to ‘tune’ your iPhone camera via add on lenses. This is the review of one that is a snug protective case from Griffin that has a lens allowing the iPhone to take close up picture clearly.
Your first reaction may be that you don’t ‘need’ to take close up pictures. But, you may want to take a closer look at how your using your camera now.
For group shots or pictures of landscape, all is good. Try to take a picture of a piece of paper or a scratch on your car and you get a slightly out-of-focus usable-ish picture.