This one's almost a cop-out, since all Windows users should know about WinDirStat by now. This app has been out for nearly 15 years, and it's one of the most helpful tools you can use to clean up your hard drive.

It's been nearly a decade since we last checked out Lockhunter, an incredibly useful Windows app that ensures you'll always be able to remove files and folders that File Explorer refuses to delete. Developer Crystal Rich Ltd continues to update the app with useful features, but sporadically: It took around 3.5 years to go from version 3.1 of the app to version 3.2.

This app isn't something you'll probably have to use very often -- we hope -- but it's a great tool if you're upgrading your system and need to move everything from an old hard drive to a new drive.

Nobody likes an operating system that's full of unnecessary stray files, 20 annoying apps that start up when you fire up your computer, and other crap that slows down your system, makes your desktop feel disorganized, or gives you a headache whenever you're trying to work (or game). Thankfully, there are a number of free apps that can help you clean your Windows PC.

Finding a place to securely save files online or send them between computers is surprisingly difficult. Over at Digital Inspiration, Amit Agarwal uses WhatsApp as a clever workaround to store through an encrypted connection. Here's you can do it too.

Android: AirDroid is one of our favourite Android companion apps, and now it's getting a pretty big update. The coolest new feature lets you share files with people near you, even if you don't have an internet connection.

Accidents happen, especially when we’re managing our mobile storage. In the effort to free up that extra gigabyte, you might have deleted a few photos or messages you shouldn’t have. Fortunately, Enigma Recovery Professional is here to give you a safety net when you’re clearing out your storage.

Mac: If you're coming over to macOS from Windows, or you just plain prefer how Windows sorts files with the folders on top and files below, then How-To Geek points to a little setting that allows you to change how files are sorted.

Windows/Mac: If you want to move a file, whether it's a video, ebook, ringtone or whatever else, from your computer to your iPhone, you'd usually need to use iTunes. Waltr allows you to skip iTunes, or skip wires altogether.

If you're not in the habit of regularly backing up your data, do it now. Cloud storage company Backblaze has made it even easier with insanely cheap storage space that you can connect directly to your NAS.

File managers may be a dime a dozen on Android, but Solid Explorer stands out from the pack. With advanced features for managing and browsing your files, both on your phone and remotely, it's our new favourite file manager.

Mac: Gemini, our favourite duplicate file finder for Mac, got a big update today that modernises the interface and improves the file scanning algorithm so it can find more duplicate files even when they're not named the same thing.

Mac: Hazel has long been our favourite tool for automating file cleanup on your Mac, and today it's getting a little easier to use with live previews and support for syncing services.

OneDrive for Windows shows you all the files in your locker — but they’re not necessarily all stored locally on your machine. If you want to make sure they are all synced and available the next time your Wi-Fi connection disappears, here’s how to do it.

Mac: Over the weekend, nasty, but small scale little piece of ransomware was found in the Transmission BitTorrent client. One way to avoid this type of malware infection is to verify the checksums for anything you download. Blogger Jacob Salmela created a script for the Mac file manager, Hazel that verifies downloads automatically.

Dear Lifehacker, Is there any way of advanced sorting files in Windows 10? For example, I want to sort by file type first, then by Name then by Date. Using the shift click function doesn't seem to work for me. Please help!

Chrome: When you're browsing for files online, it's always a bit annoying to have to download something, then open it up in a third-party application just to view it. Docs Online Viewer lets you open up most major file formats you come across right in Chrome.

Android/Windows: Pushbullet is already a great way to bridge the gap between your devices, but now it's getting easier. In the newest version, you can remotely browse your computer's files and retrieve them without being at your computer.

Mac: If you've been using OS X El Capitan for a while, you might have noticed that the old option to "Secure Empty Trash" is gone from the trash can's right-click menu. There's a pretty good reason why, but it's still possible to do it you don't mind digging into the command line.