> There is not yet a way to build a messaging service that has both features [content-aware features like URL detection, spell-checkers, web browsing for dumb c

> There is not yet a way to build a messaging service that has both features [content-aware features like URL detection, spell-checkers, web browsing for dumb clients, targeted ads to fund free services, etc] AND [pure] privacy [in the US]. If you did it on the client, and not on the server, you could provide those features without reading messages, or breaking end-to-end encryption.