Working out how to monetize mobile will be crucial, warns Jeff Sica, chief investment officer of Sica Wealth Management. "To ensure long-term growth, Facebook needs to generate more revenue from mobile users who represent the largest percentage of growth," he explained, in an email to TheStreet. "In order to achieve this revenue, they must increase the time mobile users spend online to justify higher advertising fees. They must also shrink ad size for mobile users to increase the number of users." "Facebook needs to make a full-scale effort in further monetizing not only the site's advertising revenue opportunities, but a major bang for their buck is to do the same in monetizing advertising revenues on the mobile side," added Scott Sweet, senior managing partner at IPO Boutique, also in an email. "Facebook has acknowledged that they have not been satisfactory in this area." Facebook, which has 900 million monthly active users, said that its mobile products were used by 488 million users in March. The company, however, acknowledged in the regulatory filing for its IPO that mobile does not currently generate meaningful revenue. Sweet adds that, with IPO money flooding in, Facebook should make boosting mobile ad revenue a top priority. The Menlo Park, Calif.-based firm, which raised its IPO price range earlier this week, expects net proceeds of $6.4 billion, assuming a price of $36, the midpoint of its projected range. Bullish voices, however, predict that Facebook can dominate mobile. Sterne Agee analyst Arvind Bhatia, for example, recently said that Facebook could offer significant investor upside, citing rapid growth in mobile advertising, boosted by smartphones and tablets. Key to success in this area, though, will be Facebook's ability to forge multiple deals with a host of companies. "We are devoting substantial resources to developing engaging mobile products and experiences for a wide range of platforms, including smartphones and feature phones," explained the company, in its S-1 filing. "In addition, we are working across the mobile industry with operators, hardware manufacturers, operating system providers, and developers to improve the Facebook experience on mobile devices."