You invoke it with a key press that doesn't infer with other shortcut keys, like Win+Q.
It display a small window at the location you want. You type a few letters of a command shortcut. It autocompletes it. Hit Return, the application is launched.
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Pro Can be set to be invisible
For those that do not like the looks of the app it can be set to be invisible so users do not have to look at it.
Con Manually have to set up what applications it will be able to launch
It only supports the applications you add (those you use really frequently) with the shortcut of your choice.