1. A method of updating a wireless device , comprising: a wireless device receiving , at a first location, a notification indicating that an update package is available for the wireless device, the update package comprising a plurality of versions of an update; the wireless device transmitting, in response to receipt of said notification, device-specific information to a server system, the device-specific information comprising compatibility information relating to the wireless device; the wireless device receiving data specifying a download location of a version of the update from the server system, the version having been selected , based on the compatibility information; and the wireless device using the received data to access said the selected version of the update ; and the wireless device receiving, based on a download restriction, at a predetermined location different from the first location, the selected version of the update from the server system.