Facebook may be the most-downloaded free application on the iPhone, but today the company’s chief technology officer Bret Taylor seemed more excited about the opportunities offered by the mobile Web and HTML5.

Taylor was speaking today at the Inside Social Apps InFocus conference in San Francisco (he’s pictured above at Facebook’s f8 conference last year), where he said that mobile will be the “primary focus” of the Facebook platform team this year. Facebook has said for a while now that it wants to be the “social layer” in all mobile applications, and while Taylor acknowledged that Facebook could still do more on that front, he highlighted improvements Facebook has made recently, particularly the single sign-on feature that it announced in November.

Moving forward, Taylor said that Facebook has been feeling some pain in supporting so many different platforms. If the company wants to roll out a new feature, it has to add it on Facebook.com, across its various mobile and tablet websites, and across its multiple mobile applications. And if that’s a problem for Facebook, it’s also a problem for any other developer.

“Over the long term, most people really view HTML5 as the future platform that we’re going to be looking to,” Taylor said. He said that tech companies in Silicon Valley are probably a little ahead of the reality in their focus on HTML5, but HTML5 products are going to be “a huge amount of our investment over the next year”, not just spending on Facebook itself but also on developer tools.

The debate about the advantages of HTML5 (the latest version of the basic format of the Web) versus native apps is one that’s been going on for a while, and to be clear Taylor didn’t sound like he was coming down definitively on one side or the other. But it still seems significant that he was so pro-HTML5, since Facebook has had such success on the native side, and since Facebook’s former iPhone developer famously went on a rant about the limitations of HTML5.

Taylor didn’t just talk about mobile. He said that in 2010, Facebook’s main focus for the platform was on the user experience, and that the team succeeded in cutting back spam in users’ newsfeeds and messages by 95 percent. This year the company is turning its attention to growth. He cited Zynga’s game CityVille, which reached 100 million users in 43 days, as an example of how quickly an app can grow now.

VentureBeat's mission is to be a digital town square for technical decision-makers to gain knowledge about transformative enterprise technology and transact. Discover our Briefings.