????商務(wù)社交網(wǎng)站LinkedIn和在線存儲(chǔ)服務(wù)商Box.net也有HTML5應(yīng)用，不過(guò)他們采用這項(xiàng)技術(shù)的原因和亞馬遜有所不同。亞馬遜的云閱讀似乎一心一意想成為Kindle用戶最重要的網(wǎng)絡(luò)應(yīng)用，但LinkedIn可能僅僅是想填補(bǔ)Android和iOS應(yīng)用之外的空白。換句話說(shuō)，即便用戶沒(méi)有Android和iOS設(shè)備，他們也能獲得和原生應(yīng)用相差無(wú)幾的功能。Box.net新開(kāi)發(fā)的網(wǎng)頁(yè)應(yīng)用程序也是這個(gè)目標(biāo)。Box.net是一家位于帕洛阿爾托市的云存儲(chǔ)提供商。雖然Box.net在自己的主頁(yè)上使用了不少HTML5編碼，但該公司最近聘用了一批新的工程師之后，才開(kāi)始全面采用這項(xiàng)新技術(shù)。Box.net首席執(zhí)行官艾倫?列維稱，“我們也許應(yīng)該在一年前就支持HTML5。”他認(rèn)為HTML5日益強(qiáng)大的工具應(yīng)用使網(wǎng)頁(yè)、云計(jì)算和桌面、類客戶端軟件之前的界限越來(lái)越模糊。

??? 但這并不意味著HTML5沒(méi)有缺陷。與原生應(yīng)用相比，HTML5應(yīng)用通常會(huì)有不少限制。拿LinkedIn舉例來(lái)說(shuō)，雖然功能相差不大，但HTML5應(yīng)用的用戶界面明顯要遜色不少。此外，一些移動(dòng)設(shè)備上的配件，例如攝像頭，目前仍是HTML5的“禁區(qū)”。 LinkedIn移動(dòng)產(chǎn)品負(fù)責(zé)人喬夫?雷德芬解釋稱，“一般來(lái)說(shuō)，在某些特定領(lǐng)域，原生應(yīng)用的表現(xiàn)更好，例如多媒體圖片和照片就是如此。有時(shí)候使用HTML5的難度更大一些。還有一些領(lǐng)域，例如隨時(shí)間不斷展開(kāi)的‘無(wú)限列表’，用原生代碼處理就要便捷得多。”Box.net的列維也承認(rèn)一些特定編程任務(wù)很難用HTML5實(shí)現(xiàn)，例如獲取iPhone和iPad內(nèi)置的Safari瀏覽器以實(shí)現(xiàn)文件上傳。

????另一個(gè)難題是分發(fā)。蘋果應(yīng)用程序商店（App Store）和谷歌安卓市場(chǎng)（Android Marketplace）之所以流行，一定程度上是因?yàn)樗鼈兘档土嗽鷳?yīng)用的準(zhǔn)入門檻?，F(xiàn)在，除了谷歌初出茅廬的Chrome應(yīng)用商店，我們還沒(méi)發(fā)現(xiàn)其它有分量的網(wǎng)絡(luò)應(yīng)用商店。而且消費(fèi)者對(duì)HTML5也知之甚少，他們可能僅僅了解亞馬遜、蘋果和谷歌這些品牌。

????可以肯定的是，隨著各家公司直接比較各自的設(shè)備和市場(chǎng)，從而實(shí)現(xiàn)自我定位，HTML5有望發(fā)揮關(guān)鍵性的作用。新的HTML5應(yīng)用可能還要好幾年才能應(yīng)對(duì)處理大量數(shù)據(jù)的嚴(yán)峻任務(wù)，例如視頻編輯等。與此同時(shí)，越來(lái)越多的大公司可能會(huì)發(fā)現(xiàn)這種技術(shù)的靈活性和低廉的成本讓人難以抵抗。

????譯者：項(xiàng)航

????LinkedIn (LNKD) and Box.net's HTML5 apps, meanwhile, use the technology for different reasons. While Amazon's Cloud Reader seems intent on becoming the primary web app for Kindle users, LinkedIn's is merely supposed to complement apps developed for Android and iOS. In other words, users who don't own either type of device will still get functionality that approximates the native app. Same goes for Box.net's new web-based offering. Although the Palo Alto-based cloud storage provider uses some HTML5 coding in its main site, it didn't fully embrace the Web technology until more recently thanks to a new wave of engineers. "We probably could have supported it a year ago," says Box.net CEO Aaron Levie. He says HTML5's increasingly powerful tools blur the lines between Web and cloud, desktop and client-like functionality.

????That doesn't mean the technology doesn't face obstacles. HTML5 apps are often limited when compared with their native counterparts. In LinkedIn's case, the feature sets are similar but the user interface is noticeably less flashy. Some mobile device's assets, like the camera, remain off-limits to HTML5. "Generally, there are certain areas where native is going to do better for you, like media photos and pictures," explains Joff Redfern, LinkedIn's mobile product head. "It's sometimes a little harder to get at via HTML5. Other areas, like say, 'infinite lists' that scroll with dates that continue on and on, are handled a lot more gracefully in native code." Box.net's Levie admits certain programming tasks are still difficult to achieve in HTML, like getting the iPhone and iPad's built-in Safari browser to allow file uploads.

????Another problem is distribution. Apple's App Store and Google's Android Marketplace are partly popular because they keep the barriers to entry low for native apps. Currently, there aren't many equivalent web app stores besides Google's fledgling Chrome app store. And, consumers don't have an awareness of HTML5, the way they might of the Amazon, Apple or Google brands.

????What's certain is that HTML5 will likely play a pivotal role as companies position themselves vis-a-vis each others' devices and marketplaces. It may take years before new HTML5 apps tackle more rigorous tasks that process lots of data, like video editing for instance. In the mean time, more and more major firms are likely to find the technology's flexibility and low costs too tantalizing to resist.