After perusing our must-have Windows apps page, a plucky MakeUseOf reader emailed us suggesting that we put together a list for both Windows and Linux users.

When I originally switched from Windows to Ubuntu I was very interested in these cross-platform apps. After more than 10 years loyalty to Bill’s operating system, I had built up a trusted roster of often used software ““ but some of it was Windows only.

Here’s a selection of quality free software that works on both Linux and Windows machines.

Multimedia

VLC

The media player that just works. Most of the Internet has harped on about how good VLC is for years now, despite the program remaining fairly unchanged and well….a bit plain. Don’t let that put you off ““ simplicity is the key for this powerhouse of a video and music player.

If you’ve got a movie to watch or an album to listen to, rest assured, regardless of operating system, VLC will run it. A lightweight, codec-rich media solution that you should already have installed.

SMPlayer

An alternative to VLC, SMPlayer also does a stellar job of providing smooth, simple playback of your media. A frontend for the popular MPlayer, SMPlayer offers a slightly fancier interface and an improved playlist over VLC.

Features like automatic file resuming, a video equalizer, filters, sync control and the ability to search Open Subtitles directly within the program make this a very impressive package.

Boxee

Justin can’t get enough of Boxee, and I’m beginning to see why. Not to be confused with the set-top box you plug into your TV (that’s the Boxee Box) Boxee is a free media centre application for your Windows, Linux or even Mac computer.

Once installed you can simply use it as a front-end for accessing your local media, or plug your PC into your TV and access everything in your living room. You could even make your own dedicated Boxee Box out of an old PC. Fancy that, the Internet has arrived on your telly!

Web & Communication

Chrome / Firefox

Rarely do I group such applications together ““ especially when there’s fanboys lurking in the shadows, but Chrome and Firefox are two awesomely cross-platform browsers.

Chrome now keeps all your bookmarks synchronized with your Google Account, meaning you can log in from either OS with all your favourites intact. The Firefox 4 Beta offers a new feature called Firefox Sync which does the same thing.

Both Firefox and Chrome perform well under Windows or Linux (I find Chrome even faster on Linux), although you’ll need to install your extensions again.

Thunderbird

Especially useful to those who dual boot between Windows and Linux who demand a powerful email client, Thunderbird is the perfect solution. As modern Linux distributions can easily access data stored on a Windows NTFS partition, Thunderbird can be told to store all data on your Windows partition which in turn can then be accessed from a Linux environment.

This means you will never be out of sync with your email, even if you reboot your PC into another operating system. Clever, huh?

Deluge

One of the better cross-platform BitTorrent clients out there, Deluge is available for all 3 major operating systems. It has an interface reminiscent of uTorrent, and includes support for full encryption, a remotely controllable Web UI, plugins and more.

You can even control multiple instances of Deluge across the network, making it a very powerful BitTorrent solution for those that need it. Check out our full low-down for more information.

Pidgin

If you’re after an all-in-one instant messaging client for your PC, then give Pidgin a go. Formerly known as GAIM (way back when), Pidgin offers support for a startling amount of IM services.

These include AIM, Google Talk, ICQ, MSN and Yahoo as well as some more obscure platforms and an IRC client if you’re that way inclined. As Digsby‘s not ready for Linux yet, Pidgin fills its boots nicely.

Adobe Air & Java

Technically not apps at all, Adobe Air and Java both work on Windows and Linux to provide cross-platform compatibility with a multitude of programs. As these programs use a framework, there is no need for separate Windows and Linux versions – they should just work.

With great apps like Tweetdeck at your disposal, you’re bound to find something you like. We’ve got some great Adobe Air picks right here, and more information on the Java platform here.

Office & Graphics

OpenOffice

It doesn’t have the “next-gen” interface seen in Microsoft’s latest Office suite, but OpenOffice gets the job done. For those of you with the simple demand of an Office suite that opens a multitude of file formats (including all Microsoft Office files) then look no further.

There are 5 programs included in the suite:

• Writer ““ A simple yet powerful word processor.
• Calc ““ A spreadsheet program.
• Impress ““ A presentation application.
• Draw ““ For creating diagrams and graphics.
• Base ““ A database management tool.

Funnily enough, I’m using OpenOffice Writer for this very article.

GIMP

GIMP stands for GNU Image Manipulation Program, and it is the Linux equivalent of Photoshop. The interface can be tricky at first, especially if you’re used to Adobe’s efforts but there’s plenty of guides and documentation to help you on your way.

For those of you who would prefer a more Adobe-like interface from the get-go, then try GIMPShop, a hack that alters the interface to make GIMP more closely resemble Photoshop.

InkScape

For vector artists on a budget, InkScape steps up to the mark. Essentially a free equivalent to Corel Draw, Adobe Illustrator and Xara X, InkScape is a community developed and driven project with versions for Windows, Linux and even Mac OS X. InkScape uses the W3C standardised Scaleable Vector Graphics format (.SVG) to save files, and as such is compatible with a wide range of advanced features.

Do you have any favourite software that works cross-platform? Maybe you’re searching for a Linux equivalent to a much loved Windows program? Get it off your chest in the comments.

Thanks to reader Robert Backlund for suggesting this article. Have you got an article you would like to see? Why not get in touch? Don’t forget MakeUseOf Answers for those tough techie questions!