When you hold Command and press Tab, the Application Switcher overlay appears above all other open windows on your desktop, and remains visible until you release the Command key. Letting go switches you to the last active app, prior to the one you were just using.

Repeatedly tapping Tab with the Command key held down cycles you through the list of apps in the Application Switcher from left to right, while releasing Command takes you to the selected app. You can also press the right and left arrow keys to move the selection box forwards and backwards. A two-finger drag on a trackpad does the same thing, or you can use your mouse cursor to highlight an app in the list and then click to select it.

Bring back a minimized app

While the Application Switcher allows you to cycle through open apps, selecting an app with minimized windows doesn't automatically restore those windows. To do that, activate the Application Switcher and navigate through the row of icons. With the desired app highlighted, press and hold the Option key, then release the Command key. This action will restore the minimized window of the app in question.

Close and hide apps via the Application Switcher

Pressing the H key in the Application Switcher hides all the windows of the selected app (pressing the H key again reveals them). It's a neat way to quickly clear a space on a desktop cluttered with windows. This method streamlines window management by avoiding minimization. By invoking the Application Switcher again you can switch back to the hidden app.

Lastly, highlighting an icon in the Application Switcher and tapping Q has to be one of the fastest ways to individually quit open Mac apps.