On Thursday morning, Mark Zuckerberg stood smiling in front of a crowd of journalists and employees at Facebook’s headquarters and put months of rumors to an end. “Today we’re finally going to talk about that Facebook phone,” he said, referring to long-swirling speculation that the social network was secretly developing a device to rival the iPhone. He immediately clarified, adding, “More accurately, we’re going to talk about how you can turn your Android phone into a great, simple, social device.”

Zuckerberg proceeded to unveil an app called “Home” that takes over the home and lock screen of Android smartphones, essentially building functionality around the social network. Home’s “cover feed,” for example, fills the home and lock screens with status updates from Facebook friends, which you can double-tap to “like.” Notifications shown on these screens include a picture of the friend who posted each of them, and Facebook messages and SMSs turn into “chat heads”—headshots that float in bubbles on a phone’s display, making it easy to carry on conversations while using apps.

Home will be available for free download on April 12 and will initially be available on just a handful of smartphones that run the latest versions of Google’s Android software. There actually will be a “Facebook phone,” too: The HTC First, which comes with Home integration and runs on AT&T’s network. It will also be available April 12, and will cost $100 with a two-year wireless service contract. 

The app makes a lot of sense for Facebook, and fits in with its much-mentioned “mobile first” strategy. But now that the Facebook phone is here, it’s not altogether clear how many of its billion-plus users will really want it.

Home, as Zuckerberg and several other Facebook executives made clear, makes your phone about people, rather than about apps. So, if you set it as your default home screen, it’s always there, showing full-screen status updates from your friends all of the time. Even if you spend a lot of time using Facebook on your phone—and you probably do, since as Zuckerberg pointed out, about a quarter of the time we spend on our phones is devoted to checking Facebook and Instagram—Home is a big change.

Ramon Llamas, a mobile analyst at research company IDC and self-described Facebook lurker, doesn’t see himself using Home immediately. But he does believe it will appeal to “Facebook fanboys and fangirls”—those already checking Facebook on their smartphones many times a day. “There are some avid users out there who are going to be like, ‘You know what? I wouldn’t mind upgrading to that,’ ” he says.

Home comes with some innovative features. The “chat heads” feature presents people you’re sending messages with through Facebook or via SMS as little bubbles that you can move across your smartphone’s display, and they appear atop any app you open. This makes it easier to switch back and forth between, say, getting a map to the movies and letting your friend know where to meet you by the theater. Because of this sort of easy access, Gartner analyst Brian Blau expects many regular Facebook users to give the app a try.

But since Home doesn’t offer an easy way to toggle back to the built-in Android home-screen experience, it might be offputting to those who already like the Android experience as it is.“Just as there are a number of Facebook fanboys and fangirls, there’s also a terrific number of Android fanboys and fangirls,” Llamas points out.

Jan Dawson, chief telecoms analyst at Ovum, thinks it could be a tough sell for another reason. While Home will make it easier to share information with friends, it will also allow the social network to collect more data about what you’re doing on Facebook. And since Facebook depends on user-targeted ads for revenue, eventually, Home will include ads, too.

“That presents the biggest obstacle to success for this experiment: Facebook’s objectives and users’ are once again in conflict. Users don’t want more advertising or tracking, and Facebook wants to do more of both,” Dawson said in a statement.

Regardless, Home won’t even be available to everyone for a while. At the start, it will only be built into the aforementioned HTC First, and available for download on the HTC One X, HTC One X+, Samsung Galaxy S III, and Samsung Galaxy Note II (it will also work on the HTC One and Samsung Galaxy S4 when those are available). A version of Home for Android tablets is coming in a few months, Facebook says. There is no sign that an app like Home will be made available for iPhone users.

At least one benefit to all the data Facebook will gather is that Zuckerberg will quickly discover how many of them “Like” his update to the modern smartphone.