Stop all docker containers and apps and then remove them:
docker ps -aq | xargs docker stop | xargs docker rm
Remove all docker images:
docker rmi $(docker images -a -q)
Remove all docker volumes:
docker volume rm $(docker volume ls -qf dangling=true)
The Linux command, xargs, reads lines of text from the standard input or output of another command and then turns them into commands that are then executed.