Spring is upon us! Well, that's what the calendar says, at least. As we make our way through the unpredictable weather of the next few weeks, the new season is also a great opportunity to dress our iPhone anew—and what better way to find your next case than to peruse the latest Macworld weekly roundup of iPhone protection?

Aeris: The Rail (iPhone 4 and 4S; $110) is a bumper made of aerospace-grade aluminium. It features a patent-pending screwless construction that makes installation a breeze and provides lasting protection. The case is finished in a high-polish anodized color and comes in red, blue, orange, green, pink, purple, black, or silver. A number of optional accessories add more features, such as a kickstand, screen protector, and so on.

Concord Keystone: The Keystone ECO AmigoCase (iPhone 4 and 4S; $70) combines a protective case with a battery pack that boosts your iPhone's battery talk time by 7.5 hours, audio-playback time by almost eighteen hours, or standby time by a whopping 195 hours. Interestingly, the AmigoCase is designed so that the battery resides in a holster—perfect for clipping to your belt or to a carrying bag—so that it adds battery life without weighing down your handset while in use. It comes in white, black, blue/black, or pink/white.

Edge Design: The Alfa (iPhone 4 and 4S; $99) brings together a strong, high-grade aluminimum chassis with a polymer band to provide protection for the back and sides of your iPhone. The chassis comes in anodized silver, blue, black, orange, green, or black with pink highlights. If you want a more-customized look, additional interchangeable bands are available for $9 each.

Incase: The Sports Armband Deluxe (iPhone 4 and 4S; $45) brings together a detachable protective case and an armband for a solution that protects and carries your handset whether you are out exercising or just going about your daily routine. The armband is designed to fit a range of arm sizes and is perforated for breathability and comfort. The Sports Armband Deluxe comes in black.

Incipio: The Specialist (iPhone 4 and 4S; $35) is a semi-rigid case that features a co-molded, polycarbonate-and-TPU construction for excellent feel and, thanks to the combination of glossy and matte materials, a very stylish look. The case comes in glossy/matte black, white/grey, blue/grey, or green/grey.

Kon Design: The iPup (iPhone 4 and 4S; $30) features a cute, animal-inspired design that adds a convenient pocket to your iPhone for storing a credit card. The case comes with a protective card that keeps your credit card safe from magnetic fields without blocking the functionality of RFID-enabled payment media. The case is available in seven different motifs, and comes with a Home-button cover, a complimentary button that features the same character as the case itself, and free wallpaper for your home and lock screens.

Photojojo: Feeling nostalgic? The iPhone Rangefinder (iPhone 4 and 4S; $65 to $99) will take you back to a time when taking a photo didn't involve electronics. In addition to simulating the look of an old-school point-and-shoot camera, this case features a real rangefinder and a shutter button that depresses the iPhone's volume button to take photos the way we used to way back when. If that weren't enough, a higher-end version comes with three magnetic lenses that let you take wide-angle, macro, and telephoto pictures.

TrtlBot: The Kidsafe (iPhone 4 and 4S; $25) is, as its name suggests, a case designed with children in mind. In addition to offering sturdy protection, it is designed to flip around so that the home button is covered and cannot be pressed—thus helping curb the destructivity of those tiny, but very active, hands. It comes in black, white, or green.

X-Doria: The Cubit (iPhone 4 and 4S; $25) is a back case made of TPU plastic that features an open grid construction. Into the grid's boxes you can fit a number of interchangeable colorful squares, making it possible for you to create your very own pattern of green, blue, and orange. The case comes in black or white, and it includes all the appropriate camera and port openings.