A system for managing a smoking substitute device (10, 110) including: a first smoking substitute device (10, 110); a mobile device on which an application is installed, wherein the first smoking substitute device (10, 110) is configured to communicate with the application; the system includes an application server, wherein the mobile device is configured to communicate with the application server, and wherein the application server is configured to store validity state information associated with the first smoking substitute device (10, 110) from which it can be determined, using ID information identifying the first smoking substitute device, whether the first smoking substitute device (10, 110) is valid for use; wherein the first smoking substitute device (10, 110) is configured to store ID information identifying the first smoking substitute device (10, 110); wherein the first smoking substitute device (10, 110), application and application server are configured to: determine (S503, S514) whether the first smoking substitute device (10, 110) is valid for use based on the ID information identifying the first smoking substitute device (10, 110) and the validity state information associated with the first smoking substitute device (10, 110); and if the first smoking substitute device (10, 110) is determined to not be valid for use, issue a disable signal (S504, S515) configured to disable the first smoking substitute device (10, 110); wherein the disable signal is configured to disable the first smoking substitute device (10, 110) non-permanently, if the validity state information associated with the first smoking substitute device (10, 110) indicates that the smoking substitute device is invalid and should be disabled non-permanently; wherein the disable signal is configured to disable the first smoking substitute device (10, 110) permanently, if the validity state information associated with the first smoking substitute device (10, 110) indicates that the first smoking substitute device is invalid and should be disabled permanently. a first smoking substitute device (10, 110); a mobile device on which an application is installed, wherein the first smoking substitute device (10, 110) is configured to communicate with the application; the system includes an application server, wherein the mobile device is configured to communicate with the application server, and wherein the application server is configured to store validity state information associated with the first smoking substitute device (10, 110) from which it can be determined, using ID information identifying the first smoking substitute device, whether the first smoking substitute device (10, 110) is valid for use; wherein the first smoking substitute device (10, 110) is configured to store ID information identifying the first smoking substitute device (10, 110); wherein the first smoking substitute device (10, 110), application and application server are configured to: determine (S503, S514) whether the first smoking substitute device (10, 110) is valid for use based on the ID information identifying the first smoking substitute device (10, 110) and the validity state information associated with the first smoking substitute device (10, 110); and if the first smoking substitute device (10, 110) is determined to not be valid for use, issue a disable signal (S504, S515) configured to disable the first smoking substitute device (10, 110); wherein the disable signal is configured to disable the first smoking substitute device (10, 110) non-permanently, if the validity state information associated with the first smoking substitute device (10, 110) indicates that the smoking substitute device is invalid and should be disabled non-permanently; wherein the disable signal is configured to disable the first smoking substitute device (10, 110) permanently, if the validity state information associated with the first smoking substitute device (10, 110) indicates that the first smoking substitute device is invalid and should be disabled permanently. determine (S503, S514) whether the first smoking substitute device (10, 110) is valid for use based on the ID information identifying the first smoking substitute device (10, 110) and the validity state information associated with the first smoking substitute device (10, 110); and if the first smoking substitute device (10, 110) is determined to not be valid for use, issue a disable signal (S504, S515) configured to disable the first smoking substitute device (10, 110); wherein the disable signal is configured to disable the first smoking substitute device (10, 110) non-permanently, if the validity state information associated with the first smoking substitute device (10, 110) indicates that the smoking substitute device is invalid and should be disabled non-permanently; wherein the disable signal is configured to disable the first smoking substitute device (10, 110) permanently, if the validity state information associated with the first smoking substitute device (10, 110) indicates that the first smoking substitute device is invalid and should be disabled permanently.