Everyone recognized the need for an iPhone case when No. 4 rolled into town, and whether you're concerned about antenna issues or protecting that sensitive Gorilla Glass, there are plenty of options out there. Here's a look at four iPhone 4 cases that offer everything from minimalist protection to help with the iPhone 4's antenna issues to rugged defense against scratches and grime.
The Belkin Shield Micra Case from Belkin ($24.99)
If you're shy about throwing any kind of ugliness over your iPhone 4's natural beauty, the Belkin Shield Micra Case might be a good fit. This case is clear plastic, which allows your iPhone's je ne sais quoi to shine through. You could do better in the protection department, as the Belkin 
Micra Shield really only protects the back of the iPhone 4, leaving the front exposed to possible drops. And while it's nearly unnoticeable at first, the shield scratches easily, which eventually results in a scuffed look.
The Bumper from Apple ($29.99 or free, depending on where you fit into Antennagate)
Apple's custom "Bumper," essentially a rubber band that covers the iPhone's stainless steel band/external antenna, is about as simple a solution to the antenna problem as you'll find. However, it's probably not going to save your dearest from an unexpected fumble on the concrete. Depending on your confidence in Gorilla Glass producing the kind of durability the name suggests, the bumper is arguably as minimalist a solution as you're going to get without a developing your own force field app.
The Otterbox Defender ($49.95)
Otterbox cases are one of a kind, and the Otterbox Defender for the iPhone 4 is no exception. While the Defender's bulk may prohibitive in everyday use, it offers peace of mind for when you're traveling or outdoors. To be sure, the resulting combination of Otterbox Defender and iPhone 4 is not the slick beauty designed by Apple designer Jonathan Ive. Still, if you're looking to maintain the beauty beneath, the Defender is a good bet. Otterbox's unique two-piece system offers a tight fitting plastic case that completely covers the touchscreen with no loss of responsiveness, as well as a rubber outer covering that plugs all ports and the like in an effort to keep out the grit and grime. If you're a worrier when it comes to your iPhone, this might be the case to put you at ease.
The Vapor from Element Case ($79.95)
The Vapor is a custom case. It's made of lightweight aluminum, comes in two pieces, and requires some assembly (four small screws secure the phone into the case). The design is gorgeous. The Vapor actually adds to the iPhone 4's aesthetics, and that's saying something. On the other hand, the case itself is a disappointment on the reception side. Apparently aluminum interferes quite a bit with a signal and after installing the case, I was unable to get anything but an EDGE signal pretty much anywhere that I went. The problem was at least partially fixed by putting a small piece of non-conductive duct tape over the antenna on the lower left portion of the iPhone 4's exterior antenna. Still, it's a tough to recommendation at $79.95.