Stairways Software (http://www.stairways.com) has released Keyboard Maestro 5.0, anew version of its productivity enhancer for Mac OS X. The upgrade revs the user interface and engine of the app.

It also adds control flow such as While loops and If/Then/Else statements, as well as permanently stored variables and a complete calculation engine. Version 5 also includes an extensible library of pre-made macros, with a variety of macros that you can build upon. Also new is undo/redo support and revisions, so you can try out new macros with confidence.

Using Keyboard Maestro's macros you can: control applications, windows, or menus; insert text; open documents, applications or URLs; execute scripts; control the system or iTunes; and more, all with the touch of a key, click of the mouse, periodically or at specific times, when an application is launched or running, or even over the Internet using Keyboard Maestro's built in web server.

Using Keyboard Maestro's Program Switcher and Window Switcher you can cycle through applications or windows, closing, hiding, launching, and more. The software lets you close or hide multiple windows or applications. Using Keyboard Maestro's Clipboard Switcher, you can select from a number of named clipboards, storing information away for later retrieval.

Keyboard Maestro 5.0 requires Mac OS X 10.6 or greater and an Intel Mac. New customers can purchase Keyboard Maestro for US$36. Version 5.0 is a paid upgrade from previous versions. Customers who purchased Keyboard Maestro after March 1, 2011, have been issued a free upgrade to Keyboard Maestro 5.