Backswimmers range in size between .5 to 1.5 cm. They have large eyes, back legs with log hairs that help them to swim, and a convex dorsum (back). Backswimmers also have wings that allow them to get up and find a new body of water to hunt in. Because it is difficult for them to actually distinguish between types of water, they are often seen in swimming pools.
Backswimmers prey on other insects and sometimes even small vertebrates, like tadpoles. As nymphs, they will consume each other. They are actually a quite beneficial group of insects because they consume mosquito larvae. So if you find one in your swimming pool, scoop it up and let it go!