My very favorite software developers have put up a few online music programs for free, they run as Java apps in a browser, so no need to download anything:
The Seventh String Metronome
http://www.seventhstring.com/metronome/metronome.html
The Seventh String Tuner
http://www.seventhstring.com/tuner/tuner.html
The Seventh String Tuning Fork
http://www.seventhstring.com/tuningfork/tuningfork.html