It’s the end of the week, but that doesn’t mean an end to learning more about your favorite Apple devices. Each week, the Friday Five takes a quick look at a Mac OS X or iOS app to point out five things you may have overlooked before.

Earlier this week, The Rocket Yard posted a review of WiFi Explorer, a Mac app that is used to troubleshoot WiFi networks and optimize their speed and throughput. That got me thinking of a topic for this week’s Friday Five — apps that are useful for fixing or troubleshooting issues on Macs. Instead of just focusing on one OS X or iOS app, this week we’ll look at five sharp tools for your Mac toolkit!

Of all the duplicate finders we tried out, dupeFinder was the simplest that still packed an impressive punch. To start a scan, you simply add a folder to the main window and hit “Scan.” Easy peasy. After a minute or two, you’ll get a list of all the files the app found duplicates of.

1.) DaisyDisk
This app is fresh in my mind this week because I used it to quickly resolve a problem on my 27-inch iMac. I was working away when I saw a warning appear on the screen telling me that my startup disk was running out of space. Considering I had noticed that I had over 250 GB of free space the day before, I was very concerned.

I immediately shut down every running app I could see and then fired up DaisyDisk ($9.99). This app scans any drive — not just your startup drive — and displays a “daisy-like” graphic showing where all of your disk space is being used. In my case, I quickly noticed that 254 GB of space was being used by one app. That Mac app captures screen action and turns it into a GIF animation for easy distribution; in this situation, it had somehow launched itself and ate all of my available drive space.

Not only did DaisyDisk find the culprit, but it helped me to quickly delete all of the individual GIF screenshots it was taking to make its “movie”. All told, this only took about 15 minutes out of my day where it could have turned into a catastrophe.

Daisydisk Find Duplicates Online

2.) My Net – Network Scanner
With the proliferation of Internet-connected devices of all sorts in our homes and offices, it’s sometimes hard to find the IP address of each and every device on your network. That’s where My Net – Network Scanner ($4.99) comes in.

This app doesn’t have the nicest UI, but it works very well and does a tremendous job of finding every IP device on your network. Even better than some free apps I had found that required the installation of a Java toolkit on my Mac before I could run them, My Net also identified what most of the devices were by name.

While there are still some items on the list I’m not sure about, for the most part I was able to tell what I have connected to the network, see what IP ports are open (if any), ping the devices to make sure they’re working, and even connect to the device if it has a built-in web server as many webcams and routers do.

3.) OnyX
This free, donation-supported utility is a favorite of mine. It’s been updated over the years for each and every version of OS X, and the developers are currently working on the El Capitan-compatible version of OnyX (version 3.1).

What does it do? How about everything you can image! It is actually three apps in one — OnyX, Maintenance, and Deeper. OnyX performs system maintenance (getting rid of log files, cleaning caches, etc…) and can be used to turn on or off hidden functions in OS X that would normally be available only from Terminal.

Maintenance is used to verify the disk and system, something that used to be available in Disk Utility but that was removed from the El Capitan version. It will also rebuild certain files that may have been corrupted, and can perform jobs like rebuilding the Spotlight search index.

Deeper is used to personalize your Mac, doing things like permanently turning off Notification Center if it drives you nuts or resetting LaunchPad if the big app icons are in some weird order you’re not thrilled about.

Daisydisk Find Duplicates List

OnyX is definitely worth waiting for if you’re already on El Capitan. If you’re still using older versions of OS X, download it now.

4.) StatsBar
Here’s another app that I consider to be a must-have on every Mac I own (only two right now…) and it’s one I recommend to friends and colleagues. StatsBar ($2.99) sits in your menu bar and can provide statistics on each and every aspect of your Mac’s operation. Want to see what the CPU is doing while you’re attempting to edit that movie? Wondering what the throughput of your network connection is? Want to clean up memory on your Mac? These and many more functions are just a click away in StatsBar.

Definitely one of my favorites, StatsBar is unobtrusive and just monitors your Mac until you need something. You can use a Yosemite/El Capitan notification widget to track your system stats as well.

5.) Gemini
My last pick is an app I wish I had purchased long ago, but I didn’t use it until recently. Gemini ($9.99) has just one purpose in life — it finds duplicate files and then removes them. The new version (1.5.12) is ready for OS X El Capitan and it not only looks at your local drive, but can check out external drives and network volumes as well.

Where I found Gemini to be extremely helpful was finding duplicates in my iTunes library and in a volume containing photos. It scans folders in a heartbeat, tells you what are likely duplicates, and makes sure that at least one instance of each file is kept safe.

Daisydisk Find Duplicates Free

While DaisyDisk is great for finding and deleting the big space-eaters in your storage, Gemini is better at looking at what’s left and determining if you have any unknown file duplicates. What’s sad is that you will find them… a lot of them.

Daisydisk Find Duplicates Search

Have any favorite toolkit apps (AKA utilities) that we haven’t mentioned here? Let us know about them in the comments.