When Mountain Lion debuted, one annoyance that surfaced with the OS was that it kept going to sleep when idle. Disabling this feature didn’t seem to work, and we had to resort to Terminal commands and apps to keep it from sleeping. What both these methods do is prevent sleep based on a time preset. Though what if you want Mountain Lion to sleep only after a certain app has finished working and quit? In other words, what if you want to prevent sleep mode as long as a particular app is running? Wimoweh is a free Mac app that lets you do just that. It prevents OS X from sleeping indefinitely, or if a particular app is running, and you can define the app(s) that will keep it awake. Wimoweh also tells you which apps are preventing your OS from going to sleep; they might be apps that you have enabled to prevent sleep via Wimoweh, or other apps that require your system to stay awake while they are working. In the latter case, Wimoweh makes it easier for you to find out which app is keeping your system awake.
Wimoweh adds a Lion icon to the Menu Bar. Click it and it will show which apps (if any) are keeping your system awake. The ‘Never Sleep Whilst Running…’ submenu allows you to select any of the currently running apps as a trigger to keep your Mac awake.
When you select an app to prevent sleep, Wimoweb reports which app is preventing sleep in the ‘Apps Preventing Sleep…’ submenu.
Wimoweh also gives you information on the power source and battery level of your Mac. This is useful because if your Mac isn’t plugged in, it will not be able to stay awake forever; the battery is bound to die out in such a case, so the app lets you know how long the Mac will stay awake under the current power source.
Lastly, the ‘Prevent Computer Sleep’ option keeps your Mac awake indefinitely (or until power runs out). Enable it and your system stays awake regardless of which apps are running.
Wimoweh is useful when you have apps that quit themselves when they have competed a task and you would like to send your system to a low power mode when that happens. Some apps allow you to shut down your Mac when they have completed a task, but very few apps support that option. With Wimoweh, you can enable all apps to trigger system sleep when they quit.