Although I don’t expect a post-apocalyptic world where all land has been covered in water anytime soon, it’s springtime here in the U.S., with its flower-bringing showers. And summer, with its accompanying water sports, is just around the corner. Which may leave you struggling to choose between leaving your iPod at home or risking it getting wet. Worry no more, as it’s also the time of year when vendors release cases designed to keep your portable player safe and dry. Here’s a look at four such cases: three for the third-generation (3G) iPod nano and one for any iPod.

I tested the three “waterproof” cases by submerging them in a bathtub of water for 10 to 15 minutes. Note that none of the cases include waterproof headphones, although you can buy those separately, if you need them, from H2O Audio, OtterBox, and SwimMan.

OtterBox iPod Nano 3rd Gen Armor Case

OtterBox recently split the company’s iPod case lineup into two lines, Armor and Defender. The Armor models extend the existing line of truly waterproof (to a 3-foot depth) iPod cases, and, in fact, the iPod Nano 3rd Gen Armor Case (US$40) is essentially an updated version of the OtterBox for iPod nano (2nd Generation). You insert your nano into the case by opening the lid and sliding the iPod in until its headphone jack connects firmly to the 1/8″, stationary headphone plug inside; an external, pass-through headphone jack on the bottom of the case lets you plug in your headphones. A gasket forms a watertight seal when you close the case, keeping out water, dirt, and other elemental baddies. Rubber bumpers inside the case provide excellent shock protection for your iPod, and the plastic case itself is virtually crushproof.

When your iPod nano is in the Armor case, the Hold switch is inaccessible (as is the dock-connector port, of course). However, a thick membrane over the iPod’s Click Wheel lets you control playback and volume. For the most part, it’s easy to use the Click Wheel through this membrane, although the Click Wheel opening is fairly small; those with large thumbs may find that the thick edges of the opening make it difficult to scroll consistently. And the Armor’s protection comes at a price: at 4.4 by 2.8 by 0.6 inches, an Armor-encased 3G iPod nano is considerably bulkier than the iPod alone.

The back of the case features a removable belt clip that also functions as a place to wrap excess headphone cable. Also included is a detachable fabric lanyard. An optional armband ($15) can be used in place of the Armor’s belt-clip.

The Armor is an excellent case for using your nano in wet, dusty, or dirty environments, as well as for taking it places where it’s likely to get dropped, tossed, or stepped on.

OtterBox iPod Nano 3rd Gen Defender Case

OtterBox’s other case for the 3G nano, the iPod Nano 3rd Gen Defender Case ($30), is part of the company’s new Defender line of water-resistant cases. (We previously reviewed the iPhone version.) Instead of the bulky, water-tight design of the Armor series, the Defender line uses a slimmer, water-resistant design that consists of a hard-plastic internal shell covered in a silicone external “skin.” Your 3G iPod nano fits between the two pieces–front and back–of the clear-plastic shell, which snap together when closed. You then stretch the black-silicone skin over the shell to provide a layer of shock protection (and to ensure the pieces of the rigid shell don’t separate).

Like the Armor, the Defender leaves the nano’s Hold switch inaccessible. The iPod’s screen and Click Wheel are visible and usable through openings in the case, protected by a thin, clear-polycarbonate sheet. This sheet is considerably thinner than the membrane used on the Armor case, making it much easier to use the nano’s Click Wheel. My only complaint about the sheet is that the inside surface is easily-scratched: I saw a slight blemish on the inner surface over my iPod’s screen, and when I tried to brush it off, my fingernail left an even worse mark. (The outside of the sheet is quite resistant to scratching.)

Although the Defender leaves the nano’s headphone jack and dock-connector port accessible, separate silicone flaps can be fastened over these openings when not in use. (Note that although you can connect Apple’s USB dock cable when your nano is in the Defender, you can’t use other dock-connector accessories.) One thing that worried me a bit about the case is that these flaps are connected to a very thin strip of silicone that stretches across the bottom-front of the case. Pulling on the flaps, removing the skin from the shell, and placing the shell in the skin all stretch this thin strip. The strip didn’t break during my testing, but it didn’t look like it could take a lot of repeated stress. Thankfully, OtterBox provides a lifetime warranty.

If you don’t need the true waterproof protection of the Armor case, the Defender offers slightly less shock protection, along with less protection against dust, dirt, and water, in a much-less-bulky package.

H2O Audio iN3 Waterproof Case for the iPod nano 3rd Gen

Whereas OtterBox’s Armor series of cases are aimed at those want protection from overall rough conditions, H2O Audio’s line of iPod accessories are designed specifically for in-water use; the iN3 Waterproof Case for the iPod nano 3rd Gen ($80) is rated as waterproof down to 10 feet. Like the OtterBox Armor, the iN3 uses a two-piece clamshell design with a stationary headphone plug that fits into your nano’s headphone jack and passes the audio signal to its own headphone jack on the exterior of the case. When you close the case, a silicone T-seal locks out water and other substances; the iN3’s clasp includes a locking mechanism that prevents the clasp from being opened unless you purposely hold a spring-loaded switch in the Unlock position. Like the Armor case, the iN3 adds considerable bulk; unlike the Armor case, there are no rubber bumpers inside the iN3 for additional shock protection.

In order to increase the iN3’s level of protection, H2O Audio uses a solid-plastic enclosure–no membranes here. The iN3’s plastic is crystal-clear everywhere, which makes the case quite attractive, although it also means that scratches are more noticeable with the iN3 than with a case, such as the Armor, that uses a textured surface. In lieu of a membrane over the iPod’s Click Wheel, H2O uses a mechanical, rotating dial with a middle button and four buttons around the edges corresponding to the Click Wheel’s five buttons. When you spin the metal dial with your finger, a metal piece on the inside of the case “touches” the Click Wheel. The biggest advantage of this mechanism is that it works even when the case is underwater (or wet out of the water). On the other hand, sometimes I had to press fairly firmly on the dial to get the expected response.

The iN3 package also includes a number of accessories. A neoprene, elastic band lets you wear your iN3-encased nano on your arm, and a plastic belt clip can be installed using two included screws. You also get a replacement T-seal.

If you want a case specifically for water sports, the iN3 is tough to beat. For an amphibiously-active lifestyle that includes rough-and-tumble land sports, the Armor offers a bit more shock protection (and costs quite a bit less).

iFrogz iBagz

At the other end of the water-protection (and price) spectrum from the iN3 is iFrogz’s iBagz ($12), which the company describes as “water resistant bagz.” And, spelling aside, that’s pretty much what the iBagz is. Instead of a rigid case, the iBagz is essentially a thick-plastic bag with a waterproof seal and a pass-through headphone connector. You open the bag, insert your iPod, connect iBagz’s cable to your iPod’s headphone jack, and then seal the bag up tight. The sealing process works much like a dry bag you might take on a kayaking trip; you close two Ziplock-like closures, roll down the top edge three times, then secure the top with a strip of Velcro.

You connect your headphones to the dangling headphone jack on the outside of the bag. The bag’s plastic is thin enough that you can still control your iPod, including scrolling using the Click Wheel. You can even use an iPhone’s touchscreen through the iBagz. However, the iBagz’s headphone plug doesn’t fit the iPhone’s recessed headphone jack; you’ll need a headphone adapter. Even then, you’ll be able to use the iPhone only as an iPod; the iBagz’s headphone cable doesn’t pass phone/voice signals. I also found it to be a minor hassle to get an iPod–especially full-size models–into the bag and connected.

iFrogz claims the iBagz is made of “commercial grade heavy-duty plastic to withstand puncture by sharp edges and foreign objects”; it did indeed feel tough in my testing. On the other hand, because it’s a simple bag, the iBagz offers little protection from shock or crushing. (Although the iBagz is big enough that you can actually fit a smaller iPod–nano, shuffle, or mini–inside its own case inside the iBagz.) An included adjustable lanyard lets you wear the iBagz around your neck.

Although the inside of the iBagz stayed dry during my bathtub test, iFrogz advertises the case as being water-resistant, not waterproof. In other words, this is a simple, inexpensive accessory designed to keep your iPod dry in “splashy” situations–in the rain, by the pool, while boating, etc. And it does that well, despite its obvious limitations.

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