Camera or mirror more accurate what you look like?

Yes, I've read a couple of similar questions to mine, but I'm still confused. Either the mirror is what people see you as (although some say it's reversed so I'm taking that's how it is when you take a picture of yourself.) I just feel really insecure and ugly when someone takes a picture of me from the back camers of an iPhone/iPod and when I take them on snapchat I look a lot more decent. Which one do I really look like.

A photo is a specific moment in time. Also, a camera lens can distort how you look. A mirror is not locked into a specific view, so you can see yourself, notice something, and then change it. So if you slouch and see yourself in the mirror, you stand up straighter. But if you slouch all the time, a photo of you slouching is more accurate. But if you take a bad photo, at the moment you are making an odd face, that may not be how you look all the time.

so sometimes it is one, sometimes it is the other, and sometimes it is neither.

While what Matt said is true, your brain has a effect upon how you view yourself. Anorexics see themselves fat in a mirror. There are body perception disorders.

You will never see what you actually look like with a mirror because the reflection is inverted. Some study I read in my psychology class a long time ago said that most people like how they look better in the mirror than how they actually look.

The good thing about mirrors is that they capture your image to the point where your eyes can't see how it is fake. When you take a picture with a camera, it is restricted to dots of color called pixels. So the image looks less real. It's like looking at a blurry picture, except it's good enough for people to not complain.

Pictures give you a more accurate suggestion of what you look like, mirrors are more precise in recreating what you look like inverted to the human eye.

A mirror image is REVERSED and not a true life image. Only you generally see yourself in a mirror so how can it be what other people see too?
A photograph is a TRUE image of yourself and is how everyone else sees you.

You look strange in a photo because you are more used to seeing your reversed image in a mirror.