When it comes to selling bags and packs for the iPad, most bag makers are either creating products specifically designed to carry an iPad (these fit the iPad well but aren't very useful without an iPad inside) or repurposing "netbook" bags (these tend to have padded compartments more suited to a netbook's chunky frame). While Tom Bihn has indeed produced one iPad-specific bag—the Ristretto ( )—the company has generally taken a different approach with its iPad-compatible line: Create great bags that can be used for carrying an iPad but that can also be used on their own.

That's certainly the case with the Co-Pilot, a compact (12 by 10 by 5 inches) shoulder bag that performs admirably as a carry-on, a day bag, or—when used with the protective sleeve or case of your choosing—an iPad bag. Made of either 1050d U.S. ballistic nylon (in steel gray, indigo blue, crimson red, or black) or Japanese Dyneema/nylon ripstop fabric (in gray with a grid pattern), with #8 YKK splash-proof zippers, the Co-Pilot's construction and materials feel ready to handle any abuse you might dish out. The inside of of the Co-Pilot sports ripstop fabric in a lighter, different color—yellow or gray, depending on the bag's exterior color—to make it easier to see whatever it is you're toting.

As with the "laptop" area of many Tom Bihn bags, the large, zippered compartment that fits your iPad—located on the back half of the bag—isn't padded. As noted above, this is to avoid adding bulk that you won't want when not carrying an iPad or netbook. (The Co-Pilot weighs only about a pound when empty.) Instead, you use your favorite iPad folio, sleeve (zippered or not), or shell/skin for impact protection, while the Co-Pilot shields the iPad from the elements. This large compartment easily holds an iPad encased in even a bulky shell such as the OtterBox Defender, along with a couple books or a thick stack of files or magazines. The pocket also provides two large, vertical pouches for stashing, say, a few paperback books.

The front of the bag features three large, vertical, zippered pockets. The left pocket includes a slim, Ultrasuede-lined pouch for your phone or media player, while the right pocket hosts four slots for pens and other slim items. Each of these two pockets is large enough to hold your TSA-approved 1-quart toiletry bag.

The middle pocket was clearly inspired by my favorite feature of Tom Bihn's Synapse backpack. While the pocket can be used for any decent-sized item, such as a compact umbrella or a packable jacket, it's specifically designed as an easy-access pocket for a water bottle. The pocket easily accommodates a 20-ounce bottle, and a small eyelet drain at the bottom of the pocket helps keep the rest of your belongings dry if your bottle ever leaks. Because the pocket is in the middle of the bag, the weight of your water bottle doesn't make the bag unbalanced and awkward to carry, and the design of the pocket lets you leave it open without compromising the shape or stability of the bag.

Each of the Co-Pilot's four zippered pockets features an o-ring for clipping keys, a carabiner clip, or one of Tom Bihn's myriad organizer pouches.

On the back of the bag is a document pouch large enough to hold a couple magazines for quick access. The pouch has a horizontal zipper about two-thirds of the way down that, when unzipped, lets you slide the Co-Pilot over the handle of your rolling suitcase. I like that Tom Bihn has positioned this zipper about three inches from the bottom of the bag, rather than along the bottom edge—the higher position means you can still use the pouch for magazines or other documents while the bag is attached to your suitcase handle.

In addition to a thick, padded handle on top, the Co-Pilot includes Tom Bihn's standard padded shoulder strap, but you can upgrade to the $30 Absolute Shoulder Strap when ordering. The bag ships with metal zipper pulls, but the company includes cord pulls that can be attached to the metal pulls or, if you prefer, can replace the metal pulls entirely.

There are plenty of iPad-specific bags out there; the Co-Pilot isn't one of them. Instead, it's versatile travel/day bag aimed squarely at iPad owners. It's not inexpensive, but it's superbly made, and you're likely to get a lot more use out of it than a bag designed just to carry your iPad.