Uninstalling applications on a Mac is simple, in theory: Just drag the icon from the Finder to the trash. In practice, though, doing that leaves files behind—caches and other hidden things can take up hundreds or even thousands of precious megabytes. Pearcleaner is a free and open source application that can find such files and delete them while you're uninstalling software.
There are other applications out there for this—we've talked about AppCleaner in the past, for example. I prefer Pearclearer, on balance, because of its easy-to-understand user interface and a few advanced settings I haven't seen elsewhere.
To get started, simply install the application and open it. You'll see a list of all the software you've installed in the left panel—you can even see how much space each app is taking up. Click any app and you'll see a list of files or folders related to that app.
Everything is checked by default, but you could optionally decide to keep some things around if you know what you're doing. For example, if you're deleting a game but might want to play it later, you could keep the saved files around. It's nice to have the flexibility. You can also use an application like this to set an app to the factory settings: Just delete every file except the application itself. In most cases that should wipe all settings, allowing you to start over—I've fixed a few broken applications this way.
You don't have to rely on the list; you can drag any application to the Pearclean window to see more options. This is useful if an application you store outside the usual folders isn't showing up, though you can also optionally add folders for Pearcleaner to look at in the settings.
Speaking of the settings, there are a few things worth enabling in there. If you install Mac software using Homebrew, there is an optional integration that will clean up Homebrew-related settings for the apps you delete. There's also an optional Finder extension, which allows you to right-click an application in order to uninstall it using Pearcleaner.
I freed up a bunch of space on my device by opening this application and deleting a few large applications I don't user anymore. Give it a shot—I bet you'll find some space too.
