There are quite a few things a good SLR would do than a (stock) smartphone. I think there is like some Venn Diagram of things that an SLR would be good at, and things that a phone would be good at, and though there's some overlap in the middle, there are a lot of things that both do better than the other.
1) Smartphone lenses are fixed focal length and usually pretty wide angle. My 5s has the 35mm equiv of 25MM focal length, pretty wide. It sucks for portraits, which should be 70-120mm (35mm equiv). Sucks for distance shots as well. I was on vacation and saw a pretty moon shot, I wanted it in the background. So with a 25mm (equiv) lens, we had huge heads, and there was a pale dot off in the distance.
2) Most phones are also fixed aperture, I've only seen f/2.2 on my shots. Pretty wide open. Hyperfocal anyone?
3) Exposure controls are on screen. You have to dick around with them as you're composing, tapping the screen and making your phone shake.
There are a bunch others, those are just the first off the top of my head.
Now, this may not make your statement false. You may not care about any of those, so your phone is equivalent functionality to you. But there still is a loss.