Abstract: A system and a method respectively for customizing wireless communication units for use in wireless communication systems. The wireless communication units are generic and include a device for enabling establishment of contact with a switching arrangement and a handling device including a program executor. Software relating to the wireless communication units is provided in a number of storing devices accessible over a global data communications network. Location information is provided, and, with use of the location information, software relating to a particular generic communication unit is downloaded via the switching arrangement using the global data communications network to the communication unit.