We conducted this research in order to be able to cross analyse the results of these happiness indexes with online behaviour. Our research - in France, Germany and the UK - combined a traditional online survey, which matched the happiness question wording of the official well-being surveys with passive tracking data (i.e. web and app behaviour tracked across the participants phones, tablets and PC/laptops). It was vital here to obtain real behavioural data because when it comes to Internet usage, declarative data may be biased or inaccurate (even if you are ready to face the truth, it is difficult to estimate the time you spend online each day, on every website, every app, etc.). Our research combined traditional and new passive methods.