[Question] Approaches for collecting and analyzing data about yourself?

As step one in actually improving my life, I am embarking on a massive expedition for data, both about myself (e.g. triggers for moods, when I feel the most focused) and about the effects of certain interventions (e.g. meditation, taking short naps). However, I’m not quite sure what the best way is to go about this.

I’ve been using the iPhone apps iMoodJournal and Track Your Happiness for about a week for hourly check-ins, and they’ve worked fine, but they don’t quite have the flexibility and breadth of functionality I’m looking for.

Ideally, I’d have something that would let me add check-in entries about my mood, focus/​productivity, state of physical discomfort, or anything else I’d want to measure on a numbered scale. I’d also like to be able to enter in these check-ins things that I’d done in the previous hour and then see an analysis of how these activities/​interventions affect me (e.g. how my state is different when I do X vs not-X not just at that moment, but in the hours after as well).

People who have done something like this: what was your approach? Is this much precision necessary? Does something like I describe exist?

My general question is this: what are some ideas for ways to systematically notice and track your internal state to find correlations between events/​actions and your state?