Information processing device being a chip card and comprising: - a first means for storing information in a read-only memory; - a second means for storing information in rewritable memory; - a plurality of applications (8.4,8.5 and 8.6) stored in the first read-only memory information storage means; - an operating system (8.2) comprising a set of commands, including a means for invoking one application out of the plurality of applications, said application being identified by an application identifier (2.1), the application invocation means using the identifier associated with an application to determine a data structure (2.2) in the rewritable memory containing a reference to the application to be invoked (2.3); characterized in that, the device further comprises: - at least one first and one second application (3.3, 3.4), out of the plurality, associated with one and the same application identifier (3.1); - swapping means (8.3) making it possible to change the application effectively invoked in a call to the invocation means using this given identifier (3.1), out of the first and second applications (3.3, 3.4) associated with a given identifier (3.1) and comprising means for copying in the data structure (2.2), in place of a configuration data structure referring to the first application having to be invoked by means of the identifier, a configuration data structure referring to the second application having to be invoked by means of the identifier, the swapping being executed by overload of an existing command out of a set of commands of the operating system or being executed by the addition of an additional command out of the set of commands of the operating system. - a first means for storing information in a read-only memory; - a second means for storing information in rewritable memory; - a plurality of applications (8.4,8.5 and 8.6) stored in the first read-only memory information storage means; - an operating system (8.2) comprising a set of commands, including a means for invoking one application out of the plurality of applications, said application being identified by an application identifier (2.1), the application invocation means using the identifier associated with an application to determine a data structure (2.2) in the rewritable memory containing a reference to the application to be invoked (2.3); - at least one first and one second application (3.3, 3.4), out of the plurality, associated with one and the same application identifier (3.1); - swapping means (8.3) making it possible to change the application effectively invoked in a call to the invocation means using this given identifier (3.1), out of the first and second applications (3.3, 3.4) associated with a given identifier (3.1) and comprising means for copying in the data structure (2.2), in place of a configuration data structure referring to the first application having to be invoked by means of the identifier, a configuration data structure referring to the second application having to be invoked by means of the identifier, the swapping being executed by overload of an existing command out of a set of commands of the operating system or being executed by the addition of an additional command out of the set of commands of the operating system.