Facebook co-founder and CEO Mark Zuckerberg offered some of his company’s strategy on Tuesday – but kept many details a secret.

In his first appearance in public since May’s disappointing IPO, followed by the stock trading at about half of the initial price of $38 a share, Zuckerberg admitted to being disappointed.

"The performance of the stock has obviously been disappointing," Zuckerberg said in San Francisco, according to news reports.

He added that the company has made "a number of missteps," news reports added. He also addressed the need for Facebook to have more mobile offerings.

"The commitment we've made is to make the world more open and connected ...for the long term,” he said. “The next three to five years is really going to be how well we do with mobile."

"We have transitioned and are now a mobile company,” he said, adding that he also uses his phone a lot, too.

“Now we are a mobile company and all the code is being written in mobile,” he revealed in the TechCrunch interview. He also admitted the company relied too much on HTML5 when it came to mobile, previously.

He confirmed, too, that a “bunch of people” are underestimating the company, now.

“I personally would rather be underestimated,” Zuckerberg said during the public appearance in which he was informally dressed.

He added there are several long-term projects underway but did not give much in terms of details.

Zuckerberg also repeated that Facebook will not offer a phone.

In August, TechZone360 reported that shares of Facebook set a record low in trading.

The record low price came about after early investors in the company were able to sell their stock for the first time ever.

Over 270 million Facebook shares were able to be traded in August – following three months where sales could not take place. In contrast, 421 million shares were sold in Facebook’s disappointing IPO on May 18. In addition, over 1.4 billion more shares – either held by early investors or Facebook employees – will be able to be traded by the end of the year, Reuters added.

In a related matter, Zuckerberg also faced the fact that his fortune fell to a new low in August. It was estimated at $10.2 billion at one point during last month, according to the Bloomberg Billionaires Index.

TechZone360 reported that some of the latest causes of the falling stock price are the recent earnings report (which showed costs increasing more than projected) and lingering questions about future company growth. A few key executives (Katie Mitic and Ethan Beard) have left the company. In other troubling news, Facebook reported more than 83 million Facebook accounts were duplicates or fakes.

Things could change for the company if it could come up with methods to take advantage of the users who go onto Facebook via mobile devices, TechZone360 said. More generally, the company needs to find ways it can profit from its products.