A gateway may be configured to establish a first data connection between the gateway device and a client device. The first data connection may be based on a Web Real-Time Communication application programming interface. The gateway may establish a second data connection between the gateway device and an Internet Protocol (“IP”) Multimedia Subsystem (“IMS”) core; and facilitate communications, that are based on a Rich Communication Services (“RCS”) standard, between the client device and the IMS core. Facilitating the communications may include outputting communications, that are based on communications received from the client device via the first data connection, to the IMS core via the second data connection, and outputting communications, that are based on communications received from the IMS core via the second data connection, to the client device via the first data connection.