Video, Audio and Photo viewers and editors.
Videolan or VLC is an app or software program that will play nearly any video or audio format you can think of.
Paint dot Net is probably the best, free, Photo Shop type picture/photo editor, creator on the planet. With a ton of plugins that allow you to do nearly unlimited editing, you'll love it.
Audacity is probably the most popular, open source (free) audio editor/ manager in the world. If you like it, please donate. You don't have to give much as anything always helps.
Amarok was originally a linux audio player that has since been written, cross platform for Windows and Macs