How to get a whole photo to fit on iso7?

So I just got a iphone5s and when I try to make a photo for my home screen it zooms in too big, when I want the whole photo to fit. Is there a app to MAKE THE WHOLE PHOTO TO FIT or something?! And YES I TURNED OFF "REDUCE MOTION"

You need to make the photo the same aspect ratio, then it will fit. Use an image manipulation program such as Photoshop, Elements, Gimp, etc.

According to Wikipedia, here is the size/ratio you need:

5 / 5C / 5S:
4.0 in (100 mm);16:9 aspect ratio;1136 x 640 px screen resolution at 326 ppi