The invention relates to a method of expanding the functional capabilities of portable electronic devices with user friendly modes, wherein a host device is associated a quick-connect function-expanding module. In this method, at each installation of a given module, the functional expansion module and the host device recognize each other; on first installation of a given module in the host device, a series of checking operations are carried out automatically; the user can select to activate the available expansion; and once a given application is selected, the configuration and functions required for each application are stored.