1. An information processing system comprising: an information processing apparatus; and a vehicle-mounted device that is mounted in a vehicle, wherein the vehicle-mounted device includes: a microphone that picks up a speech sound, and a transmitter that transmits speech data that is generated based on the speech sound that is picked up by the microphone to the information processing apparatus; and the information processing apparatus includes: a memory which stores pictogram correspondence information in which keywords and pictogram information indicating a plurality of pictograms which correspond to the keyword are associated, and a CPU that executes pictogram selection processing which selects the keyword corresponding to text representing a speech sound that is generated by speech recognition based on the speech data from among the keywords which the pictogram correspondence information includes, and in accordance with a predetermined condition, selects one item of the pictogram information from among a plurality of items of the pictogram information that are associated with the keyword that is selected, the CPU of the information processing apparatus determines whether or not the vehicle in which the vehicle-mounted device that is a sending source of the speech data is mounted is traveling, and if the vehicle is traveling, the CPU of the information processing executes the pictogram selection processing, and if the vehicle is not traveling, the CPU of the information processing communicates with the vehicle-mounted device to cause the vehicle-mounted device to execute processing that causes a user to select one of the pictograms from among the pictograms corresponding to a plurality of items of the pictogram information associated with the keyword that is selected, and selects one item of the pictogram information that corresponds to the one pictogram that is selected by the user.