omg
I've wanted to do that, but I don't have a way of setting up my phone so that it'll stay put and then let me refocus
It takes some time but it yields amazing results. Unless you have amazing steady hands or a surface to set the camera you need a tripod though. Even slight movements will make lining up the 2 pictures a bitch. I had my camera on a tripod taking that and even me adjusting the setting made the pictures a tiny bit off.
You can't see them in the final product, but during editing I could tell.