How did imint evolve during the First World War?

Imint did not really evolve during the First World War. Most of the time during the war they used cameras attached to the side of the plane. All imagery was for tactical use, such as artillery effects and observing the front line.

It was in the interbellum when both the plane and camera evolved greatly.

Because of that the effects of imint were much bigger during the Second World War. They were finally able to use imint for designating strategic targets like industries and make the bombing more effective.