User Flows can be really helpful as the first step in designing performing apps and websites.
They can be easily or full of details, depending on what is the phase of the work.
FIRST APP SKETCH
I start making some sketch on a piece of paper of my app to understand how I would like it to work. Starting in this way helps me to think and I am also able to make any mistake because I can easily correct them with an eraser. At this stage, I am still thinking in a general way and I am designing an app without a specific target.
PROTOTYPE WITH POP
When I finished with the sketches on the paper I started to use POP. It is an app that helps you to prototype. You can easily take pictures of your paper screen and you can make animated transitions between screens. Thanks to that, you can immediately feel how the app is working and recognise instantly every single mistake since the first phase of the prototype.