[kartayyar]

About emails:

No for ads.

Yes for training models for Smart Reply, from: https://arxiv.org/pdf/1606.04870.pdf

Privacy Note that all email data (raw data, preprocessed data and training data) was encrypted. Engineers could only inspect aggregated statistics on anonymized sentences that occurred across many users and did not identify any user. Also, only frequent words are retained. As a result, verifying model’s quality and debugging is more complex.