Abstract: A vapor inhalation device (10) comprising: a housing (12) adapted to enable a user to inhale vapor, simulating the effects of smoking, the housing being adapted to receive a cartridge (14) for containing liquids; the cartridge (14) comprising or connected to a first release device (15a) arranged to vaporize and release a first liquid (A) comprising a first substance (a) from a first reservoir (16a) into the housing (12); and to a second release device (15b) arranged to vaporize and release a second liquid (B) from a second reservoir (16b), wherein the housing (12) is adapted to mix the vaporized first (A) and second liquids (B) such that the user can inhale vapor containing the first substance (a) of a particular amount; a communication unit (17) configured to receive and transmit data for controlling the inhalation device (10); a controller (18) configured to communicate with the communication unit (17) and to receive data from the communication unit; and to determine an amount of first substance (a) to