It has been specified for use in a 3GPP-compliant cellular network by the GSM Association in the PRD IR.79 Image Share Interoperability Specification.
[1] According to the specification, "The terminal interoperable Image Share service allows users to share Images between them over PS connection with ongoing CS call, thus enhancing and enriching end-users voice communication."
An Image Share session begins by end-users setting up a normal circuit switched (CS) voice call.
After the voice call is set up, terminals perform a registration to an IMS core system with a packet switched (PS) connection.
According to GSMA press release [3] interoperability between different Image Share clients was successfully tested in a multi-vendor trial in May 2007, including interworking between multiple networks.