What Were The CEOs Of Dropbox And Tumblr Doing At Facebook Today?

As we walked into Facebook headquarters today to cover the launch of its new Home app, we ran into Tumblr CEO David Karp.

We chatted with Karp, who said he got out to the Bay Area from time to time—as he should, since the blog-platform operator has investors out here, like Sequoia Capital's Roelof Botha.

Later, we spotted Karp having a chat with Zuckerberg. Then we saw Drew Houston, CEO of file-sharing startup Dropbox, talking to the Facebook CEO, too.

Former Facebook engineers Aditya Agarwal and Ruchi Sanghvi, who left to found a startup later acquired by Dropbox, where they're now top executives, also chatted with Houston and Zuckerberg. (The couple remain close to Zuckerberg, who was a guest at Agarwal and Sanghvi's wedding.)

Prominent investors also were on hand—Chamath Palihapitiya, an early Facebook executive who now runs the Social+Capital Partnership, and angel investor Ron Conway. We also saw Zuckerberg and Conway talking.

What were they doing there? The conversations weren't exactly private—they went on in full view of the assembled press corps. It would have been easy for Zuckerberg to pull people aside for some truly private conversations.

Zuckerberg is on a personal mission to meet a new person outside Facebook every day—but we're pretty sure Karp and Houston and Zuckerberg have met before.

So it felt like Facebook was sending a message. Given the news of the day, here's a theory: Facebook intends Home not just to be an app that promotes Facebook's own services. Home changes the way Android smartphone presents notifications, and that could potentially affect how other Android apps alert users to activity.

Dropbox and Tumblr already have Facebook integrations; Dropbox users can share files in Facebook groups, and Tumblr users can share posts on their Facebook profiles.

What if the eventual plan is to have Facebook Home become a platform for other apps, as Facebook is today for socially-enabled apps on the Web and mobile devices?

That would mean developers like Dropbox and Tumblr—and many others—would be linked more closely to Facebook than to Google when building apps for Google's Android operating system. And that seems worth having a conversation about.