One of the best ways to improve your photographic composition is to sketch them. A simple way to do this on your iPhone or iPad is this: when you see a photo you like, screenshot it then draw on top of it.
How to do this
There is no right and wrong in composition. Then the question is – how do you find certain photos interesting or not?
Just trace and outline compositional figures you find interesting
Look for the figure to ground, that is the silhouette of your subject against the background. Look for perspective lines, and details you find in the photo which are interesting to you.
Why do this?
First of all, I just find it personally fun and interesting to do so. While some kids may draw random pictures on a sheet of white paper, I like to do this to my photos. It is like hyper drawing, or hyper photos. That is, on top of my photos I add some thing additional.