Completely customizable tracking: t12n is intended to be very open, in the way that you can track and follow up on literally whatever you want (you're the one defining the tracking questions, and the responses to them).

Experimentation: t12n allows you to define timed experiments of behavior changes, and measure their effects on your tracking- allowing you to consequently decide which behavior changes are actually worth keeping for the long run.

Analytics: T12n provides you with analytics data that's intended to provide you with insights on your tracking.

Last (and very importantly)- notification based tracking: imho an actual game changer, in the way that it minimizes the tracking friction as much as possible: you can be notified whenever you want, and respond to the tracking question directly from the notification- literally takes less than 5 seconds!