Facebook is looking to improve the quality of its third-party applications after the company founder admitted that the social networking site had not monitored the quality of add-on software too closely.

In the past year, Facebook has struggled to control applications that use annoying or deceitful means to attract more users, like spamming people with unnecessary notifications or sharing information from people who have not given their permission to do so.

Mark Zuckerberg, CEO and founder of Facebook said: "We haven't done enough to reward the good applications or punish the applications that have just been abusive. We're going to have to find a way to ensure the applications that provide the most long-term value are the ones that are succeeding."

He was speaking at Facebook's f8 developer conference in San Francisco, where the company introduced the Facebook Verification programme. Starting in September, developers are invited to submit their applications to Facebook to see if they meet certain criteria for trustworthiness. Applications that have been verified will be marked as such so that users know they can trust them.

The company has also introduced the Great Applications programme for applications that meet an even longer list of criteria, including being "meaningful" and well-designed. The music streaming service iLike and a philanthropy application called Causes were the first to be recognised as Great Applications. The company expects to select only a dozen or so Great Apps over the next year, officials here said.

Zuckerberg also announced some new tools for developers, including the ability to submit their applications to Facebook's language-translation system, which enlists Facebook users around the world to help translate the site. Facebook has used the system to translate its own web pages into several languages, and it is now available to third-party applications to use.

Aside from some other minor announcements, including details of when Facebook Connect will be rolled out, the company offered little in the way of major developments. It did not announce a system that would allow applications to accept payments, for example, which had been widely rumoured, and it didn't announce plans to make Facebook applications available on mobile devices.

Ray Valdes, a research director with Gartner, characterised Zuckerberg's tone as "contrite" and said the company has focused on fixing what is not working well on Facebook rather than rushing ahead with new capabilities.

"There was nothing really new, the payments system was notably lacking," Valdes said. "But I think they are doing the right thing even though they will disappoint some developers. They need to clean house before they add any more rooms."

In a press conference after his speech, Zuckerberg dodged a question about when Facebook will introduce a payments platform. "I wish I knew," he said, and moved on to the next question.