There is provided an aerosol generating device configured for user inhalation of a generated aerosol, including a heater element configured to heat an aerosol-forming substrate; a power source connected to the heater element; and a controller connected to the heater element and to the power source, wherein the controller is configured to control the power supplied to the heater element from the power source to maintain the temperature of the heater element at a target temperature, and is configured to monitor changes in the temperature of the heater element or changes in the power supplied to the heater element to detect a change in air flow past the heater element indicative of a user inhalation. The controller may determine when a user has inhaled and may use this for dynamic control of the device as well as provide user inhalation data for subsequent analysis.