A method at a mobile entity for enabling use of multiple Internet Protocol, IP, Multimedia Services, IMS, the method comprising: reading (1032, 1042, 1052) data from a first IMS Subscriber Identity Module, ISIM, of a plurality of IMS Subscriber Identity Modules, ISIMs, (1012, 1014, 1016) associated with the mobile entity; the ISIMs being located at the mobile entity; the reading comprising determining if an application identifier file, EF AIDAPP, is present in the first ISIM; if the application identifier file, EF AIDAPP, is present, storing the application identifier file, EF AIDAPP, data at an internal memory of the mobile entity; and creating a binding in the internal memory of the mobile entity to bind a function at the mobile entity to one ISIM of the plurality of ISIMs, wherein the creating comprises: selecting application identifier file, EF AIDAPP, data data from the first ISIM; determining whether an indication in the application identifier file, EF AIDAPP, data for the first ISIM (1012,1014,1016) includes an indication for the function; if the indication in the application identifier file, EF AIDAPP, data includes the indication for the function, determining the first ISIM to be the one ISIM to be bound to the function and binding the first ISIM to the function; and if the indication in the application identifier file, EF AIDAPP, data does not include the function, selecting application identifier file, EF AIDAPP, data from a different ISIM of the plurality of ISIMs, wherein when the selected function is invoked, the one ISIM bound to the selected function is used. reading (1032, 1042, 1052) data from a first IMS Subscriber Identity Module, ISIM, of a plurality of IMS Subscriber Identity Modules, ISIMs, (1012, 1014, 1016) associated with the mobile entity; the ISIMs being located at the mobile entity; the reading comprising determining if an application identifier file, EF AIDAPP, is present in the first ISIM; if the application identifier file, EF AIDAPP, is present, storing the application identifier file, EF AIDAPP, data at an internal memory of the mobile entity; and creating a binding in the internal memory of the mobile entity to bind a function at the mobile entity to one ISIM of the plurality of ISIMs, wherein the creating comprises: selecting application identifier file, EF AIDAPP, data data from the first ISIM; determining whether an indication in the application identifier file, EF AIDAPP, data for the first ISIM (1012,1014,1016) includes an indication for the function; if the indication in the application identifier file, EF AIDAPP, data includes the indication for the function, determining the first ISIM to be the one ISIM to be bound to the function and binding the first ISIM to the function; and if the indication in the application identifier file, EF AIDAPP, data does not include the function, selecting application identifier file, EF AIDAPP, data from a different ISIM of the plurality of ISIMs, selecting application identifier file, EF AIDAPP, data data from the first ISIM; determining whether an indication in the application identifier file, EF AIDAPP, data for the first ISIM (1012,1014,1016) includes an indication for the function; if the indication in the application identifier file, EF AIDAPP, data includes the indication for the function, determining the first ISIM to be the one ISIM to be bound to the function and binding the first ISIM to the function; and if the indication in the application identifier file, EF AIDAPP, data does not include the function, selecting application identifier file, EF AIDAPP, data from a different ISIM of the plurality of ISIMs, wherein when the selected function is invoked, the one ISIM bound to the selected function is used.