Facebook is the largest social network. Everyone knows that. The latest statistics indicate it has over 800 million active users. The iPad is the most popular tablet. Everyone knows that, too. According to Gartner, out of 10 tablets sold this year, at least seven are iPads. What everyone fails to comprehend: The lack of an official Facebook app for the iPad. It has been one year and 10 months since the first generation iPad was released, and iPad users are still stuck with a blown up oversize version of the iPhone Facebook app. What gives? Facebook engineer Jeff Verkoeyen revealed an insider story on his personal blog to vent his frustration. Verkoeyen says the official Facebook app for iPad has been feature complete since May, but his boss decided it's still not the right time to release it. He left Facebook for Google out of frustration:

It is now nearly 5 months since the app was feature complete and I haven’t seen it released except for when the project was leaked on Techcrunch. Needless to say this was a frustrating experience for me. The experience of working on this app was a large contribution to the reasons why I left Facebook, though that doesn’t mean it wasn’t a difficult decision.

After his story was picked up by a number of tech publications, Verkoeyen said he's not unhappy with Facebook as a company. He loved working there, but wants to try something new at Google. He went on to explain that though the app was feature complete, it wasn't the final product. On why it's taking so long for Facebook to release it, TechCrunch speculates that it may be due to the strained relationship between the social network and Apple. Both companies have had several failed attempts to partner, first in iTunes's Ping music social network, then in iOS 5's social network integration. More importantly, Apple may not like the direction Facebook is taking with its mobile strategy. TechCrunch reports that Facebook had been working on a "Project Spartan" to position itself as an HTML 5-based application platform within iOS. Apple and its strict App Store policy will be removed from the loop if that project takes off. "But Apple has always wanted Facebook to release an iPad app... At first, Facebook wasn’t going to focus on the iPad. Then they decided to, but they also realized the app could be used as leverage in their dealings with Apple," wrote MG Siegler of TechCrunch. Interestingly, Mashable says that both the companies may be be working together to perfect the HTML 5 platform. Writer Ben Parr had also reported that the official Facebook iPad app may be released at the iPhone 5 announcement event. If Parr's correct, the relationship of both the companies may not be as strained as an outsider sees it. Photo: Nicholas Chan