1. A system of multi-modal transmission of packetized data in a voice activated data packet based computer network environment, comprising: a natural language processor component executed by a data processing system to receive, via an interface of the data processing system, data packets comprising an input audio signal detected by a sensor of a client computing device; the natural language processor component to parse the input audio signal to identify a request and a trigger keyword corresponding to the request; a direct action application programming interface of the data processing system to generate, based on at least one of the request and the trigger keyword, a first action data structure; a content selector component executed by the data processing system to receive at least one of the request and the trigger keyword identified by the natural language processor and to select, based on at least one of the request and the trigger keyword, a content item via a real-time content selection process; an interface management component of the data processing system to: poll a plurality of interfaces to identify a first candidate interface and a second candidate interface; determine a first resource utilization value for the first candidate interface and a second resource utilization value for the second candidate interface, the first resource utilization value and the second resource utilization value based on at least one of a battery status, processor utilization, memory utilization, an interface parameter, and network bandwidth utilization; select, based on a comparison of the first resource utilization value and the second resource utilization value, the first candidate interface as a selected interface to present the content item; convert the content item for delivery in a modality compatible with the selected interface selected based on the comparison of the first resource utilization value and the second resource utilization value; provide the first action data structure to the client computing device for rendering as audio output from the client computing device; and transmit the content item converted for the first modality to deliver the content item for rendering from the selected interface.