Default Google photo sync?

Does anyone know how to manage Googles photo sync? I've been trying to figure this out for a while and it's driving me nuts.
I'm trying to find a way to backup only photos taken by my camera and not random images on my phone.

I have found this:
https://support.google.com/plus/answer/1647509?hl=en
Which seems like the solution. But I cant find the damn photos app? Did it even come installed on this phone?

It's unbelievable how complicated a simple task like this can be. Drives me up a wall.