Facebook's ongoing IPO roadshow is happening, and co-founder Mark Zuckerberg has teased investors with a better idea of what they could expect to be key revenue drivers for the social networking site, once it goes public.

Firstly, Zuckerberg said that Facebook will concentrate on improving its mobile application, where they'll infuse other online apps into Facebook, and secondly, creating a "transformative" advertising experience".

Zuckerberg spoke at Palo Alto's Crowne Plaza, where he tried to calm investor nerves over Facebook's revenue streams. Advertising revenue and user base growth rates have begun to slow down as Facebook reaches market saturation. Zuckerberg of course calmed investors that Facebook's advertising would still drive revenues.

The social networking sites social ads, which pitch products to users that their friends have liked, are better suited to smaller mobile screens, according to the hoodie-wearing Zuckerberg. Zuckerberg pushed Facebook's mobile standing, claiming the company will be reaching out to app developers and making it easier to integrate their own services into Facebook.