After having about all the cases I could take at CES, I stumbled upon the iLid booth with a weary eye. I vaguely remembered a Kickstarter campaign a while back, and the case -- which is also a wallet -- was for the 4 and 4S-sized iPhone. It seemed like a cute idea, but these things are often better in theory than in practice. However, at CES I got a sample of the iPhone 5 version and since then I've been trying it out. It's great, especially if you like to keep a small wallet or have less stuff in your pockets.
iLid is a plastic case which puts a small chamber on the back of the iPhone. This chamber snap