Since its unveiling, many individuals have been vocal about Facebook Home concerns, speculating about privacy and what information the service many gather. To mitigate the worries and clarify the issues, Facebook has released answers to several questions that have been posed repeatedly, talking about what information it gathers, how privacy works with it, and more.
Facebook clarified that users can continue to access the social network on their handsets the same way they currently do - there's no need to use Home if you don't want it. If you do choose to use the service, you can likewise ditch it any time you want, turning it off under "Settings" or removing it from the lockscreen. This way, users can try it out, but aren't obligated to keep it.
As far as what information Home gathers, Facebook says that it collects data on how users use the service, such as what apps the user places in the Home launcher. It also pulls information about how the app is interacted with, such as commenting and liking. On pre-installed devices, Home will display notifications and Facebook collects certain information from the notification, with the exception of its content. This data is stored for 90 days, after which point indentifying information is removed.
Another big question is whether Home gathers data about other applications and how they are used. The answer is "no." In the example given, Facebook would get data about an app that is launched using the app launcher, but it would not receive any information about how that app is used. Likewise, location information is used the same way the regular Facebook app uses it, and location services can be disabled by the user. For more information, you can check out the Data Use Policy.