Abstract: The present invention relates to a device, a system and a method for measuring the lung function and the inhalation technique of a human subject, to facilitate the empowerment of patients to self-manage airway diseases, in particular asthma. The device according to the invention comprise a first part capable of measuring the time (s) and volume of air/time (v/s) exhaled from the human subject during a single inhalation, thereby providing a measurement of the lung function, and further comprising a second part capable of measuring the acceleration (m/s2) of air and volume of inhalation from the human subject during a single inhalation, thereby providing a measurement of the inhalation technique, the second part of the device further comprising means for applying metered resistance to the inhalation, the applied resistance impairing the acceleration (m/s2) of air and volume of inhalation from the human subject during the inhalation.