Disclosed is a mobile device (15) for analysing breath samples, comprising: - at least one mouthpiece (16) provided with at least one inlet opening (17) and at least one outlet opening (21) for allowing a person to respectively inhale and exhale via the mouthpiece, - at least one air filter (20) connected to the mouthpiece for filtering ambient air to be inhaled by the person, - at least one analysis compartment (19) connecting to the outlet opening of the mouthpiece and provided with at least one chemical trace detector (1), wherein the chemical trace detector comprises: at least one semi-conducting sensor(2)； at least one heating element (4) for heating the semi-conducting sensor； at least one processor (6) for controlling the heating element； and a detection circuit (7) for detecting the change in resistance of the semi- conducting sensor which is at least partially determined by the presence of at least one chemical trace which reacts in the presence of the semi-conducting sensor.L'invention se rapporte à un dispositif mobile conçu pour analyser des échantillons d'haleine. L'invention a également trait à un procédé prévu pour analyser des échantillons d'haleine, en particulier à l'aide d'un dispositif mobile ci-décrit. L'invention porte aussi sur un capteur destiné à être utilisé dans un dispositif mobile ci-décrit.
