What Window Management Options exist for OS X? I'd like to do something with my windows on OS X, where something includes options like re-arranging, moving, re-sizing, remembering positions, cloning across Spaces, etc. What options exist?

Rules


One app per answer.
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## [app name](link to website)
[App Store](link to appstore) (price)   
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Include short description about what this Window Managing app does.

What makes this Window Manager app different than the others?
Is it focused on re-sizing using only the keyboard?
Is it focused on moving using only mouse gestures?
Etc.
Spectacle
Open source, available at GitHub, accepting donations
App Store link (will not be updated past version 0.6.9)


Center = Command+Option+C
Fullscreen = Command+Option+F
Left Half = Command+Option+←
Right Half = Command+Option+→
Top Half = Command+Option+↑
Bottom Half = Command+Option+↓
Upper Left Corner = Command+Control+←
Lower Left Corner = Command+Shift+Control+←
Upper Right Corner = Command+Control+→
Lower Right Corner = Command+Shift+Control+→
Left Display = Command+Option+Control+←
Right Display = Command+Option+Control+→
Top Display = Command+Option+Control+↑
Bottom Display = Command+Option+Control+↓
Undo = Command+Option+Z

Per Spectacle' Github:

Spectacle users have recommended Rectangle as an open source
alternative.

Rectangle is maintained as of 2020.
brew cask install rectangle