Google has yet another billion-user service. Gmail, the company's longstanding email service, now has 1 billion monthly active, according to CEO Sundar Pichai on a call announcing the company's Q4 2015 earnings. (It initially hit 900 million sometime before last May.) This is seventh billion-user service for Google, which also includes Search, Chrome, Android, Google Play, Maps, and YouTube.

Perhaps more surprisingly, Pichai also said that smart replies — Gmail's automatically-generated suggested responses featured — account for 10 percent of replies through its mobile app. Please keep that in mind the next time someone quickly and curtly suggests pizza over hamburgers for dinner — there's a 1-in-10 chance your friend let a robot write that.