OS X El Capitan introduced Split View mode where two apps appear on-screen side by side. Alas, it’s limited to full-screen mode. However, an app that’s currently free for a limited time (usual price $6.99) lets you split-screen two apps on the standard desktop. It can also maximize apps to full desktop height and width without invoking full-screen mode (i.e. the behavior of the green button until recent OS X updates).
The app’s called Split Screen and is available through the Mac App Store. Once installed it lives in the menu bar, where you can click to precisely resize the topmost app to the left or right of the screen. However, the real power of the app lies in the keyboard shortcuts, which let you do this in a split second. By default the shortcut keys are:
- Resize app to the left of the screen: Ctrl+A
- Resize app to the right of the screen: Ctrl+S
- Maximize app old-style (i.e. NOT switch to full-screen mode): Ctrl+D
Note that those shortcuts use Ctrl, not Cmd – although you can configure your own shortcuts using the app’s Preferences dialog (click its menu bar icon, then select Preferences, then click in each field before typing your desired keyboard shortcut).
The app has a few extras, such as a pop-up Web search (Ctrl+G) and the ability to hide and reveal files (Ctrl+E and Ctrl+F respectively). In short, this is a nice little app. Grab it for free while you can.
- Split Screen at the Mac App Store (free for a limited period)