Gnome3 Tile Windows side by side

the keyboard shortcut is:

Superkey+Left : Tile current window to left side

Superkey+Right : Tile to the right.

Where the Superkey is often the "windows" key and the directional keys are the arrow keys.

Sadly gnome removed the keyboard shortcut for expand to full window, which used to be Superkey+Up, although you can double-click on the title bar to toggle an app to full screen.

For Macs try BetterTouchTool

it's free and it allows you to create many more keyboard shortcuts as well.