There is provided a method involving a portable medical device (1), being carried by a user and a mobile phone (2) carried by the same user, the method comprising the steps of a) the mobile phone (2) at a time point (first time point) determining a geographical position of the mobile phone (2), and providing the geographical position and the first time point to a server (4) via a data connection, or the mobile phone (2) having its position determined by the cell network (3), and the cell network (3) providing the position and the first time point to the server (4), then b) the server (4) using the position and the time point to retrieve position-specific data for the time point, then c) the server (4) using a the data from step b. to determine whether the medical device should be serviced or replaced. There is also provided a system, a server and a mobile phone.
