Apple's Mission Control option in OS X Lion is useful for keeping track of windows and open applications, but its default view can be a bit limiting, especially if you have multiple applications and windows open.
For instance, if you open a few windows in Safari and TextEdit, then Mission Control will group both Safari's and TextEdit's windows and stack them on top of each other, making them difficult to see. If you then open a few other programs, the stacks of Safari and TextEdit windows in Mission Control will become even smaller, sometimes to the point where you cannot make sense of their contents.
While you can mouse over the windows in the stack and click them to bring them to the front, doing this is an impractical way to manage large collections of windows.
This problem happens because Mission Control allocates equal screen space to all open applications, instead of giving the one with more windows the room it needs to display its items. This makes the management of applications convenient, but encroaches on the convenience of managing windows.
As a result of this limitation, people may resort to the less convenient option of switching to an application and then invoking Expose on it (four-finger swipe down on multitouch trackpads, or Control-down arrow on keyboards) to view only its windows, since doing this will show larger previews of the application's windows.
While Mission Control may seem limited in this manner, it actually does have a couple of options to compensate for this limitation and allow you to better preview the contents of individual windows:
- Spread out application windows
By default Mission Control will show an application's windows stacked on top of each other with only the first two of them being spread out. However, if you place your mouse over the application and then scroll up (with a two-finger swipe or with a scroll wheel), then the application's windows will spread out farther so you can see more of them. In situations where you have only one or two applications open that each have multiple windows open, this can be exceptionally useful.
- Quick-Look a window
Even if you spread out an application's windows by using the scroll action, if you have many applications open then you may still have a problem viewing windows. In these cases, you can use Mission Control's window preview option, which is similar to the Quick-Look view in the Finder. To invoke this, in Mission Control just hover your mouse over a desired window and then press the space bar when it is outlined in blue. The window will zoom to show you its contents, from where you can then press the space bar again to collapse it or click it to bring it to front.
This feature in Mission Control is not advertised too well by Apple, but is a feature that makes Mission Control much more usable for those who keep many windows open at once.