The Facebook application is by far the most important application on both the iPhone and the iPad. Without the Facebook application, my own opinion is the iPhone would never have become as important as it is. It’s the single most widely used application. It’s so heavily used compared to other apps that I have been told by someone who thought he knew the data — this is highly secret data and I don’t know the actual numbers — that more than half of all usage of the iPhone of apps, other than those provided by the phone itself like telephony and email, is coming from Facebook. And on the iPad, too, it’s just a huge, huge part of usage. So in a way, Apple and Facebook are joined at the hip, and I think that’s one reason why Zuckerberg and Jobs have been spending time together. That is kinda depressing.  But if you don’t believe it, check these numbers: Remember how Steve Jobs announced in June that there were over 100 million iOS devices sold?  Considering a few percent of those were lost, broken or decommisioned, what percent of those 100 million+ iOS devices would have active Facebook accounts?  99,125,680 is Facebook’s current tally.