Why won't my iphone record in HD?

I didn't change the settings or any thing but my iphone won't record in HD no matter what. Does anyone know what I can do to get it to work so I don't have to render my my videos all the time

Your iphone camera is not some $500 camera with interchangeable lenses. There's no HD switch, only one mode. The iphone takes great pictures and videos as is considering it was intended for a phone. If you are serious of phone and video editing, don't use an iphone.