I’ve been using Moodscope to track my mood for the last year. This is the only quantified-self approach to tracking my emotional state that I’ve found long-term worthwhile.
Most other apps that support mood tracking just as “How was your day?” and ask you to rate 1-5 on a classic Likert scale. That kind of prompt seems to prime for the outside view of my life. I implicitly substitute “How was your day?” with the questions “Am I alive, healthy, employed?” and then stoically answer 3 every day, while missing macro trends towards what Venkatesh Rao calls “failed reality maintenance”.
Instead, Moodscope presents a panel of 20 specific emotions and asks you to rate how much you identify with each from 0 to 3. The increased specificity has helped me catch problematic ruts in my state-of-mind, at the cost of 1-3 minutes of my morning routine. If I consistently rate “irritable” above 0, I know I had better focus on sleep hygiene and more exercise. If “hostile” is trending, I had better do some journalling and reframe whatever family or work situations are on my mind.
This is my last year of ratings:
The folks behind Moodscope have been running it on the side for 10 years, but they have a crowdfunding campaign going right now to fund improvements to the interface. Please give it a try and consider supporting them.
 I found Moodscope via Alex Vermeer’s excellent “Life Hacking” page. He has since removed the reference to Moodscope (I’m not sure why), but he has plenty of other good tips.
 I have “take mood inventory” in my Complice dailies and of course I keep myself accountable for doing it with Beeminder.