How should I monetize this app?
friism: I think #3 is best, especially if you let users rate individual sessions or integrate with something like Rescue Time: http://www.rescuetime.com/developersThere are good options for monetizing a free-version:1) Show sponsor sites instead of wanted site when visiting Hacker News etc. while in pomodoro2) Open an interstitial or show adds in some other way when pomodori ends.