20. The system of claim 17 , wherein the context information includes at least one of an application context, a current location of the client device, recent user activity on the client device, one or more recent searches performed by the user, and currently or recently displayed content by the client device.
17. A computer system comprising: one or more computing devices; an interface of the one or more computing devices that is programmed to receive a request to transcribe spoken input provided by a user of a client device that is remote from the computer system; a speech data repository that is accessible to the one or more computing devices and that includes data that maps linguistic features in a language to one or more elements of speech in the language; a speech recognition engine that is installed on the one or more computing devices and that is programmed to determine, using context information associated with the user or the client device, one or more hypotheses that represent one or more likely intended textual transcriptions for the spoken input, wherein the context information is determined based on information in the request; a transmitter that is installed on the one or more computing devices and that is programmed to cause the one or more hypotheses to be sent to the client device in response to the request; and a context deletion module that is installed on the one or more computing devices and that is programmed to delete the context information in conjunction with the transmitter sending the one or more hypotheses to the client device.