Simple menubar utility which provides Windows-like window snapping and controlling the window layout using keyboard shortcuts.
Also allows the creation of custom "Snap Areas" that allow for user-defined window sizes.
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Pro Custom Snap Areas
With this feature, you can move any window into the desired position, select 'advanced: create a custom snap area (using current window as template)' from the toolbar and also edit settings for the snap area. It is also possible to edit the size, position, and presentation of the drop-zone, the shortcut for the custom snap area, and a list apps for which the snap area should be available (eg: only show this zone for VLC).
BetterSnapTool is no longer free and now costs $3.