Most surveys in Ethica are prompted to you automatically, so you don't have to be worried about them. Some surveys are exceptional as they cannot be automated, rather you have to answer them anytime you prefer. For example if a study asks you to report every time you feel sick, Ethica cannot automatically detect your health and prompt this survey. The study will rely on you to report your sickness, if it happens.
To do so, a study can have one or more Actions. Each action in fact starts a survey, which allows you to report a situation. For example in the following study:
You can report three situations:
When you feel sick, you can press I'm feeling sick today to report.
When you get a flu vaccine, you can press I received a new influenza vaccine to report.
When you hear something about vaccination, you can press I heard an advisory or promotion for influenza vaccine to report.
Pressing each of these buttons starts a survey where you will be asked questions relative to the situation.