I use MoodTracker.com, a free, secure web site. It allows the user to track Core Mood, Mixed Mood, Sleep Hours, Anxiety, Irritability, and Med Compliance. It's a private-access model, but it allows you to set up subscriptions for your support system, i.e.: pdoc, T, SO, etc.

I nearly forgot (because I never use it) there is also a page for journaling. It also allows the printing of charts to make it easier to share with docs or therapists. I highly recommend it as it's always as close as the computer. I have not tried it with a mobile device, though.