The Facebook Home app that went live on 12th April on Google play was restricted to the US users only. And now the app is available for everyone. You can download it from Google play.
Unfortunately the app may not work on many devices. I tried searching for the Facebook home app from my Micromax A116 but it did not get listed. I then tried loading the URL directly from my phone using Google play (here is the link) and I got the message your device isn’t compatible with this version.
I tried searching for the app from UMI X2 and it did show the app and I was able to download and even install it however I got the message device is not supported yet from within the Facebook home app and there is a button that will launch the general Facebook app. I got the same message when trying to run on the Wammy Passion.
For now even though the app is available you will not be able to use it as it will pop up a message – the device is not supported. Probably within few weeks or months the Facebook home app might start working on many devices.
You can follow the procedure here http://lifehacker.com/get-facebook-home-on-any-android-phone-472944847 to get the FB Home working. (Thank you Saurabh for the link).