Facebook will make a version for Android tablet computers, too, but that's not coming for months.
There won't be a version for Apple's iPhone and iPad. Apple's iOS and Mac operating systems include features that integrate Facebook's services, but Zuckerberg says doing something like Home would require a closer partnership.
By contrast, Google makes Android available on an open-source basis, free for anyone to modify, so it's easier to make changes. But Facebook says it's not making a new version of Android, a practice known as forking. Home is being built on top of Android.
Zuckerberg says Facebook isn't building a Facebook phone, saying a Facebook-centered device might sell 10 million to 20 million units at best. Rather, it's building on the existing Android system to bring this experience to a wider group of Android users.
But it is partnering with HTC to build a phone with Home already installed. Called First, the phone will have a screen that measures 4.3 inches diagonally and will work on AT&T Inc.'s 4G LTE cellular network. The phone will cost $100 with a two-year service agreement. It will go on sale April 12, with advance orders beginning Thursday.
The event comes amid rapid growth in the number of people who access Facebook from smartphones and tablet computers. More Android integration could help Facebook Inc. attract more mobile advertisers.
Facebook says ads will eventually come to this new service. It will be interspersed among the items displayed on the home screen, the way Facebook now injects ads into the main news feed showing friends' photos, links and other posts. But in this case, the ads will take up the entire display.