The number of mobile phone subscriptions has reached 5.9 billion, an impressive figure in a world of 7 billion people. Surveying the mobile and online landscape in 2011 for a year-end report (PDF), the International Telecommunications Union found that mobile phone subscriptions have now penetrated 87 percent of the entire world and 79 percent of all developing countries. Among all those mobile phone users, mobile broadband subscriptions number almost 1.2 billion. Such subscriptions have jumped 45 percent each year for the past four year and now outnumber fixed broadband subscriptions by 2 to 1. To push forward with mobile broadband, 159 nations across the world have kicked off 3G networks, though 2G coverage is still twice as high as 3G. Overall, people in developed countries typically use both mobile and fixed broadband, while those in less developed economies often have access only to mobile broadband services. Switching over to fixed broadband, one-third of the 1.8 billion household around the world now have Internet access, up from one-fifth just five years ago. In developing nations, 25 percent of all homes have a PC and 20 percent have Internet access. Among all the major nations, Korea still offers the fastest broadband access with almost the whole country enjoying speeds of more than 10 megabits per second. Further down the list, the U.S. is more of a mixed bag with a little more than one-third of the population seeing speeds higher than 10 Mbps and the rest stuck between 2 to 10 Mbps and 256 Kbps to 2 Mbps. Overall, a full one-third of the 7 billion people on the planet use the Internet, and 45 percent of them are under the age of 25. Internet use has been growing in developing countries, accounting for 62 percent of the world\'s total last year, compared with just 44 percent in 2006. China alone represents almost 25 percent of the world\'s total. Still, developing nations have a ways to go. Across the different age groups in the developing world, 30 percent of people under 25 use the Internet, compared with 23 percent of those 25 and older. But that 70 percent of the under-25 crowd not online adds up to 1.9 billion people, an open door for schools to provide access and potentially boost enrollment, says the ITU.