A good app has to offer:

* The social element – share, view, network, meet like minded people
* An element of voyeurism that makes looking at others’ stats intriguing
* A layer of analysis over the raw stats. So I drink 25 cups of water a day? What does that make me?
* Not too techie. Make the statistical side fun and accessible.
* Offer multiple and easy ways to log data. This is the boring side of lifetracking. Going online to tell an app I just had another can of coke is not really compelling and any barrier to logging data is a big turn off.
* Common units of measure. It’s great that I can creat my own unit of measure on some apps (e.g. cups of water) but then I can’t compare myself to others, which for me is more interesting. It’s not ALL about me.
* Auto-logging of life data
* Adding a location-aware dimension will make it really interesting
* Easy to use, of course
* Offer multiple ways to display data – widgets, RSS, etc.
* iPhone integration, naturally

You install a few plugins for the media software on your computer (winamp, wmp, itunes, etc) and the software keeps track of all the music you listen to, posting every track to a web service.

On the website, you can track stats about the artists, albums, and tracks you listen to most often. But the best part is that the software finds similarities between your own tastes and the tastes of other uses, recommending new music to you based on the stuff you listen to already.

I’ve discovered tons of new interesting music with it.

And as a narcissist myself, it’s fun to keep track of my stats:

http://www.last.fm/user/benjismith

“IYOUIT is a mobile application developed in Python, and running on Nokia Series 60 phones. Its aim is to make it easy for an end-user to automatically record, store, and use context information, e.g. for personalization purposes, as input parameter to information services, or to share with different types of relations, or just to log them for future use or to perform statistics on your own life.”