A method for downloading an executable application into a decoder for a digital broadcast system, characterized in that the application is stored on a portable memory card introduced into a card reader in the decoder, the decoder reading and downloading the application from the card. Data may preferably be stored in the smartcard in a broadcast data format such as the MPEG format to permit the processing of such data in the same manner as the control unit of the decoder processes data downloading by a broadcast transmission. The invention extends equally to a decoder and a memory card for use in such a method.