On a macOS system, a third-party app offers the most convenient way to use a key combination to snap an app to a side of the screen. I use the Magnet app ($7.99) on my device. Once installed and configured from the Mac App Store, the key combinations (as shown in Figure C) that move the active app to either side of the screen are:

  • control + option + left arrow, to position an app on the left, and
  • control + option + right arrow, to position an app on the right.

(Note: If you prefer not to purchase a third-party app, Apple does offer a manual way to move apps to a portion of the screen that uses app positioning options, rather than keyboard controls.)

Figure C

Photo of MacBook Air keyboard, with control, option, left arrow and right arrow keys circled in red.

The third-party Magnet app adds window positioning keyboard controls to macOS. Press Control + option +  left arrow to snap an app to the left side of the screen. (Control + option + right arrow does the same to the right.)

Photo: Andy Wolber/TechRepublic