7. The method of claim 1 , wherein the method further comprises: determining a relevant subset of the shared pronunciation lexicon based on the context of the third user device, wherein the speech-to-text conversion on the audio data is performed using the determined relevant subset of the shared pronunciation lexicon to generate the textual representation of the user speech.
7. The method of claim 1 , wherein the method further comprises: determining a relevant subset of the shared pronunciation lexicon based on the context of the third user device, wherein the speech-to-text conversion on the audio data is performed using the determined relevant subset of the shared pronunciation lexicon to generate the textual representation of the user speech. 10. The method of claim 7 , wherein the context of the third user device comprises a contact list stored on the third user device, and wherein determining the relevant subset of the shared pronunciation lexicon based on the context of the third user device comprises determining to include, in the relevant subset of the shared pronunciation lexicon, one or more pronunciations for named entities in the contact list that are also in the shared pronunciation lexicon.