The user interface that will run on the HTC First (Facebook Phone) has leaked ahead of Facebook's big reveal on 4 April.Evleaks at 9to5Google was able to score a look at "Facebook Home" - a skinned version of Android that the folks in Menlo Park have been working on.According to the leaked images, Facebook Home looks quite clean, bringing a lot of full-screen photography to the user interface. The ability to launch Facebook apps like Instagram, Messenger and more are present throughout the menus.\u00a0Code for Facebook Home leaked earlier revealed\u00a0it may work on devices other than HTC's, as references to TouchWiz were found. This may suggest Facebook Home will be available to download from Google Play, as earlier media reports have already suggested.EvLeaks further took to China social network Weibo to show off the HTC First running in bright red, plain white and baby blue.The software earlier confirmed specifications for the First. It will boast a 4.3-inch 720p screen, 1GB of RAM, a 5-megapixel camera and the dual-core Qualcomm Snapdragon S4 MSM8960 processor. It has already rolled through the FCC with AT&T bands - other carriers are currently unknown.Pocket-lint will be covering the Facebook event on 4 April to bring you the latest.