Since these phones are more computers than they are phones, Leo likes having the biggest screen he can get. It's available in black and white, but it's the same phone aside from the colors.
As far as the phone goes, it's pretty much the same thing as the Samsung Galaxy S III, except it has a bigger screen, more memory and faster processor. It also has two radios for cellular and voice so that it allows for talking and surfing at the same time on a CDMA network like Verizon. Apple didn't put this in the iPhone 5 for some reason.
As far as cases go, Leo has a folio style case that has a stand that he found on Amazon. The one he ended up using is the official Samsung case that replaces the battery cover and doesn't add to the bulk of the phone.