Twitter today decided to reveal some information about users in the U.K. According to the company, 10 million people across the U.K. are actively using Twitter, placing it in fourth place behind the U.S., Brazil, and Japan. In addition, the company revealed that 80 percent of those users are active on mobile devices, easily outpacing the global average of 55 percent. Twitter is notoriously tight-lipped about its userbase and growth, making today\'s announcement somewhat notable. Twitter defines an active user as someone who has logged into its service at least once in the past 30 days. Twitter\'s announcement today comes just a couple of months after the company revealed that it now has 140 million active users around the world. The company\'s users send out 340 million tweets each day, and average 1 billion tweets every three days. To put that into perspective, it took Twitter 3 years to hit its first billion tweets. But Twitter\'s work is far from done. The company\'s vice president of products, Satya Patel, said last month that \"everything\" his company is doing \"is oriented around getting to 2 billion users.\" With 140 million users worldwide right now, though, that might take a while.