There are a lot of good camera apps in the Windows Phone Store, most of which are better than the default app built into Windows Phone itself. For example, I use the Nokia Camera app for all my photo taking needs because I like the controls better and I think it produces a slightly better photo because of how the app renders the photo.
On my Lumia 1320 I have a camera button on the side but by default it is set to the camera app built into Windows Phone. Changing this however is easy and can be done in Settings. By changing your camera app in Windows Phone you can have your favourite camera app literally a click away.