????信號燈變綠后，我們前面的那輛車還停著不走，身邊的朋友嘆了口氣說：“我是不會只顧著智能手機而忘記交通信號燈的。”果然，那位駕駛員埋頭向下，似乎是在莊嚴地祈禱，不過更可能是在玩短信/地圖/音樂應用。這個小小的場景彰顯了移動設備對人們日常生活的影響。

??? Facebook或Twitter進入我們的生活之前，我們在排隊等候結賬之前會做些什么來打發時間？在天氣應用程序問世以前，我們如何查詢天氣預報以便在雨天不下雨的空隙遛狗？以前沒有手持終端即時訪問網頁的情況下，我們怎么解決圍繞電影和體育等瑣事的爭論？如今要依靠短信或點評網站Yammer這樣的網絡來處理的緊急工作任務以前是怎么做的呢？

????現在看來，那些日子似乎很遙遠，但對于大多數人來說，這其實也就是一兩年的光景。但隨著移動設備變得更加強大、LTE網絡變得更快，應用程序設計變得更富有創造性，我們的生活方式每個季度似乎都經歷著一系列新的、微妙的變化。我們在看電視節目的時候通過手機或平板電腦和朋友互動。我們收聽流媒體音樂服務Spotify或RDIO的同時，眼睜睜看著書架上的CD落滿灰塵。我們發現有很多工作現在可以在平板電腦上完成，而無需筆記本電腦。

????雖然所有這些變化都有點道聽途說的色彩，但移動數據增長方面的數據能夠提供佐證。瑞典電信巨頭愛立信（Ericsson）上周發布的一份報告顯示，過去兩年數據網絡上的移動流量已經翻番。思科（Cisco）本月早些時候發布的一份更綜合的報告顯示，去年全球數據網絡流量增長了70%。思科提供的一組對比數據顯示了移動領域的規模增長：2012年移動數據網絡上的流量為 885拍字節，較2000年全球互聯網總流量高出近12倍。2000年正是互聯網騰飛的時候。

????而這僅僅只是個開始。未來五年，無線數據流量將繼續以每年66%的增速增長。它意味著，到2017年，月度移動數據流量將達到每月11.2艾字節，是目前的13倍。這份報告中的其它數據彰顯了如今移動世界的巨大規模以及未來它將以多迅猛的速度繼續擴大。去年，全球大約有43億人擁有移動設備，五年后，這個數字將再增長近10億人。

????智能手機（81%）數據流量年增速將顯著提高，平板電腦（113%）數據流量年增速還要更上一層樓。不過，智能手機將繼續成為移動網絡數據的最大“食客”：2012年，移動手機占無線網絡連接設備總數的16%、無線網絡總流量的44%。2017年，移動手機將占無線網絡連接設備總數的27%，并消耗68%的無線網絡數據。

????在這些數字背后有幾點需要警惕。雖然思科的移動數據年度報告可能會被廣泛引用，但它也存在一些爭議（比如，這份報告是否能夠佐證頻譜危機可能迫在眉睫的擔憂）。歷史經驗表明，科技領域的增長預測最多也不過是有一定依據的猜測，往往會因不可預見的變化而失去準星。更重要的是，思科和愛立信的數據追蹤的只是無線網絡上的流量，而許多人已經學會盡可能通過WiFi網絡使用自己的平板電腦和智能手機，以確保流量不超出美國電話電報公司（AT&?）和威瑞森（Verizon）較為低級別的無線數據套餐的上限。

????"I remember traffic lights before smartphones," sighed a friend as we sat in traffic behind a car that remained still after the light had turned green. Sure enough, the driver's head was tilted downward as if lost in solemn prayer -- or, more likely, a texting/map/music app -- a small illustration of how mobile devices have changed everyday life.

??? What did we use to do to kill time in slow-moving checkout lines before we had Facebook (FB) or Twitter to distract us? How did we, before we had weather apps, check the forecast for breaks in the rain to walk the dog? How did we settle bar arguments on film and sports trivia without instant access to the web in our hands? How did all the urgent work tasks handled in text messages or networks like Yammer (MSFT) ever get accomplished?

????Those days seem distant now, but for most it's only been a couple of years. And yet each quarter seems to bring a series of new, subtle changes to our lifestyles as mobile devices grow more powerful, LTE networks become speedier and apps themselves more creative in design. We socialize with phones or tablets as we watch TV programs. We watch our shelves of CDs gather dust as we tune into Spotify or Rdio. We discover how much work can, after all, be accomplished on a tablet instead of a laptop.

????All of these changes are anecdotal, but the numbers on mobile-data growth back them up. A report from Swedish telecom giant Ericsson (ERIXF) this week showed that mobile traffic on data networks has been doubling for the past two years. In a more comprehensive report, Cisco (CSCO) said earlier this month that global traffic on data networks grew by 70% last year. Cisco offered a comparison that suggests how big mobile has become: The traffic on mobile data networks in 2012 -- 885 petabytes -- was nearly 12 times greater than total Internet traffic around the world in 2000, back when the web was taking off.

????And that's just the start. Wireless data traffic will continue to grow 66% a year for the next five years. That means, by 2017, monthly mobile data traffic will reach 11.2 exabytes per month, or 13 times what it is right now. Other data points in the report underscore how big the mobile world has become and how quickly it will grow to be much, much bigger. Last year, some 4.3 billion people around the world had mobile devices, a population that will grow by close to a billion in five years.

????Annual growth in data traffic will be significantly higher on smartphones (81%) and even higher on tablets (113%). However, smartphones will continue to be the biggest eaters of mobile-network data: In 2012, they made up 16% of devices connected to wireless networks and 44% of total traffic. In 2017, they will be 27% of connected devices and consume 68% of data.

????These numbers come with a few caveats. Cisco's annual report on mobile data may be widely referenced, but it is also the subject of some controversy (over whether it supports concerns of a looming spectrum crunch). And as hindsight regularly shows, growth projections in tech are at best an educated guess and are often foiled by unforeseen changes. What's more, Cisco and Ericsson's numbers only track traffic on wireless networks, whereas many people have learned to use their tablets and smartphones on WiFi networks whenever they can to stay within the lower tiers of costly wireless-data plans from AT&T (T) and Verizon (VZ).