rofi

An application launcher and window switcher. More information: https://github.com/davatorium/rofi.

Show the list of apps:

rofi -show drun

Show the list of all commands:

rofi -show run

Switch between windows:

rofi -show window

Pipe a list of items to stdin and print the selected item to stdout:

printf "{{Choice1\nChoice2\nChoice3}}" | rofi -dmenu