- Verify your startup disk
- Run system maintenance scripts
- Clear caches
- Configure hidden parameters of the Finder, Dock, QuickTime, Safari, Mail, iTunes, Login window, Spotlight and many of Apple’s applications
- Set automated system tasks
- Read command line function man pages
- Securely delete files in your trash
- Change the visibility of files, folders and volumes
- Install .pkg files without running Installer
- Run hidden OS X CoreServices applications
- Clean out old logs and other unwanted files
OnyX is a remarkably comprehensive system tweaker. If there’s an option Mac OS X keeps hidden, OnyX will provide access. You can enable all sorts of hidden features and easily modify much of your system’s functionality. It’s also very useful for fixing little quirks. There have been so many times I’ve been able to use OnyX to solve bizarre issues by clearing certain caches or just altering a few settings. It’s a very useful tool for your Mac whether you’re looking to solve problems or alter functionality.
OnyX’s exhaustive feature set makes it equally exhaustive to navigate if you’re not using it regularly. It can be hard to find what you’re looking for from time to time because it does so much. Also, when you start OnyX you’ll be greeted with a few annoying warning messages. You can argue these are necessary, but it would be nice if you received a single popup message allowing you to check or uncheck the startup operations you want to perform.
TinkerTool (free) is the most obvious competition and likely has many loyal users who consider it better. It definitely excels in ease of use. While its interface is similar to OnyX’s, it organises its options in a simpler and easier way. You’ll find things faster and more easily but you won’t have quite the vast number of options provided by OnyX. While TinkerTool definitely gives you plenty of tweaks, you’ll also find them in OnyX among many system maintenance tools. If you want more, go with OnyX. If you just want to make basic tweaks very easily, go with TinkerTool.
Secrets (free) is a preference pane that will add a database of configurable system tweaks to System Preferences. You can then set them to work the way you want and you’re done. You can also download secret packs to add additional functionality.
Got a favourite system tweaker not listed here? Share it in the comments!
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