Karabiner, previously called KeyRemap4MacBook, is a very powerful keyboard remapper for Mac OS X. In addition to simple key remapping, it has special remapping modes like Emacs-mode, SandS-mode (Space and Shift).
DoubleCommand is software for Mac OS X (a kernel extension) that lets you remap keys, in other words change the way your keyboard works. Often used to make a PC keyboard more comfortable with a Mac, swapping the Alt (Option) and Windows (Command or Apple) keys, since they are in...This app doesn't have any features at the moment.
KeyBindingsEditor is a GUI-based editor for OS X key bindings. It allows for easy editing and supports single-action bindings (one action per keystroke), multi-action bindings (multiple actions for a keystroke) and Emacs meta binding-style multi-keystroke bindings.
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