At the level that most of us are working at here, adding your own analystics is probably sufficient.
I have written PC applications in the past where a small amount of code allows me to track how long a user spends on each screen, how long it is in focus etc, and upload it to a web server for analysis. You just have to decide what is important first and focus on these elements.
I'm working on my first game that I will release on Android. I plan to have a login system (possibly FaceBook) so that I can track individual usage data. I am tracking time spent per game, score, how the score was built up, how many games in an individual session etc. This will get sent to my web server when their score is recorded.
There's threads on this forum about setting up a simple web service for sending data via HTTP.
Naphier wrote an article about his methods and experiences in the newsletter
here. I added a little insight in the editorial
here for out-of-game analytics.
Quidquid latine dictum sit, altum sonatur