Alphabet Inc's Google gave details about its policies for third-party Gmail add-ons but stopped short of fully addressing questions from U.S. senators about developers who break its email-scanning rules. How user data flows between big technology platforms such as Google and Facebook Inc and their partners has faced scrutiny around the world this year since Facebook revealed it had done little to monitor such relationships. Senators may seek further clarity on Gmail's operations at a Commerce Committee hearing about privacy practices scheduled for Sept. 26 with officials from Google, Apple Inc, AT&T Inc and Twitter Inc. Google did not immediately respond to a request for comment. Under Google's policies, software firms that create these add-ons must inform users about how they collect and share Gmail data. The lawmakers' inquiry came after the Wall Street Journal reported in July that some add-on makers did not make clear to users that their employees could review Gmail messages and that their data could be shared with additional parties. Google told senators it has suspended apps due to 'a lack of transparency to users,' without identifying violators or when enforcement actions took place. House lawmakers asked Google in a separate letter in July whether smartphones with its voice assistant tool can or do collect so-called 'non-triggered' audio in order to recognize phrases like 'Okay Google' that activate voice controls. Read more