Hi! Regarding your tracking remark, companies such as YesWare, MailTrack, MixMax (and so on) use pixel trackers. While such trackers are indeed made available t

Hi! Regarding your tracking remark, companies such as YesWare, MailTrack, MixMax (and so on) use pixel trackers. While such trackers are indeed made available through a Google proxy, the caching is overridable if you pass a no-cache header (http://blog.movableink.com/real-time-content-and-re-open-tracking-return-to-gmail/ http://blog.movableink.com/real-time-content-and-re-open-tra...). The Inbox SDK makes easier the interaction with Gmail's UI and does not transmit or index data.