An information processing device comprising: a communication unit configured to execute contactless communication with an external device and to receive a polling signal from the external device, said communication unit having a contactless integrated circuit, IC, chip; a storage unit configured to store state management information in which application information is stored in association with a respective priority level for each application; and a control unit configured to control a valid state and an invalid state of the application by managing the application information stored in the state management information based on a process command, wherein the control unit is configured to access said application information stored in the state management information based on a designated priority level associated with the application information stored in the state management information, in accordance with a determination of whether a priority level is designated in the polling signal received from the external device; cause one application to enter a valid state by adding the application information corresponding to the one application to the state management information, and cause one application stored in the state management information to enter an invalid state by deleting the application information corresponding to the one application from the state management information, wherein a respective application installed in the information processing device is executable when respective application information corresponding to the respective application is stored in the state management information so as to be in the valid state, and wherein the respective application installed in the information processing device is non-executable when the respective application information corresponding to the respective application is not stored in the state management information so as to be in the invalid state, such that the respective installed non-executable application remains installed in the invalid state. a communication unit configured to execute contactless communication with an external device and to receive a polling signal from the external device, said communication unit having a contactless integrated circuit, IC, chip; a storage unit configured to store state management information in which application information is stored in association with a respective priority level for each application; and a control unit configured to control a valid state and an invalid state of the application by managing the application information stored in the state management information based on a process command, wherein the control unit is configured to access said application information stored in the state management information based on a designated priority level associated with the application information stored in the state management information, in accordance with a determination of whether a priority level is designated in the polling signal received from the external device; cause one application to enter a valid state by adding the application information corresponding to the one application to the state management information, and cause one application stored in the state management information to enter an invalid state by deleting the application information corresponding to the one application from the state management information, access said application information stored in the state management information based on a designated priority level associated with the application information stored in the state management information, in accordance with a determination of whether a priority level is designated in the polling signal received from the external device; cause one application to enter a valid state by adding the application information corresponding to the one application to the state management information, and cause one application stored in the state management information to enter an invalid state by deleting the application information corresponding to the one application from the state management information, wherein a respective application installed in the information processing device is executable when respective application information corresponding to the respective application is stored in the state management information so as to be in the valid state, and wherein the respective application installed in the information processing device is non-executable when the respective application information corresponding to the respective application is not stored in the state management information so as to be in the invalid state, such that the respective installed non-executable application remains installed in the invalid state.