A messaging gateway (1) has a network node layer (20) which interface with mobile devices and manages context for them. A gateway node layer (30) controls access to applications and other functions such as billing. An applications node layer (25) provides requet/response mechanisms for access to applications on external servers. The network node layer (20) has a number of adapters, each associated with a type of mobile device. The gateway node layer (30) has nodes with access brokers which control access to applications according to user subscriptions, and responses are split up and routed according to adapter capabilities.