A wireless communication system, comprising a host service, a wireless router system coupled to the host service, a wireless network coupling the wireless router system and a wireless mobile communication device (“mobile device”), adaptively delivers data to the mobile device in the wireless communication system using a pull message delivery mechanism. In one embodiment, before the actual message is sent to the mobile device, a small notification message is sent first to enable the mobile device to send a pull request to the host to fetch the incoming message. In a preferred embodiment, if a data message is received at the host service outside of an active session, a corresponding notification message is sent while no session is active to provide notification that a data message has been received at host service and is ready for retrieval. Upon activation of a session, a pull request is sent from the device to the host service to fetch the incoming data message. The data message may be an e-mail message.