An aerosol-generating system for oral or nasal delivery of a generated aerosol to a user is provided, including a heater element configured to heat an aerosol-forming substrate to generate an aerosol； a power source； a controller configured to control operation of the heater element, the controller being configured to detect a change in air flow past the heater element: a first data storage recording detected changes in airflow past the heater element and data relating to the operation of the heater element； a second data storage including a database relating changes in airflow and data relating to the operation of the heater element to the properties of the aerosol delivered to the user； and an indicator coupled to the second data storage configured to indicate to the user a property of the aerosol delivered to the user.
