The app server is already in App Engine, so it was easy to just add an Event model and create an Event entity every time the user does anything that I might wan

The app server is already in App Engine, so it was easy to just add an Event model and create an Event entity every time the user does anything that I might want to track. This is what it looks like to browse the events in App Engine admin panel: http://i.imgur.com/yJTeZ.png http://i.imgur.com/yJTeZ.png The model is just 10 lines of code, and storing things there is even easier. For events that happen on client side I have to do a silent ajax request to the server to let it know what happened, similar to what Google Analytics does, but mostly everything that happens in the app already is known by the server.