I've been tracking every minute of my day for the past month. To help facilitate data entry for that project, I'm working on a simple mobile app.
This is the log, which is effectively just a list of records. Each record has a subtle category indicator, an end time, and a (hidden) emotion. I might add other layers of data later, but that's all that's being recorded at the moment. The only two interesting bits in the "add" interaction: the mini timeline underneath "Today" updates with your new record, and the new record slides in, flashes, and joins its siblings.
Let me know what you might have done differently!