Tablet computers are becoming more popular for Web browsing on the couch, watching Netflix movies in bed, or reading books on the train. But can a tablet replace a laptop for business travel? To find out, I grabbed an Apple iPad and the Lenovo IdeaPad U260, a new ultra-portable notebook with a 12.5-inch screen, and headed from Minneapolis to Los Angeles.

Getting the 1.5-pound iPad through airport security was a breeze, given that the TSA does not require passengers to remove e-readers, tablets, and other small electronics from carry-on bags for screening. Even though the IdeaPad looks more like a netbook than a laptop—it measures just 12.5 inches by 8 inches and weighs 3 pounds—I still had to remove it from my bag.

On the plane, both devices connected easily to Delta's Wi-Fi service, which is provided by Gogo Inflight Internet and costs $11 for 24 hours. You can connect only one gadget at a time, so I checked out some websites and sent a few e-mails on the notebook before switching to the iPad.

In both cases, the Wi-Fi ran at about 1MB per second, fast enough for light computing but not for downloading large files or streaming movies. The IdeaPad, which is powered by a 1.33GHz Intel Core i5 processor and starts at $899, ran faster than the iPad, which has a 1GHz processor and starts at $500.

One big plus to flying with the iPad is that it fits more comfortably on a seatback snack tray. But I prefer typing longer documents on a physical keyboard to tapping away on the tablet's 9.7-inch touchscreen. To get around that, I brought along some portable keyboards that connect to the iPad over Bluetooth. My favorite was Microsoft's Bluetooth Mobile Keyboard 6000 ($89.95), which weighs just 14.6 ounces. I paired it with Mophie's Workbook case ($49.95), which lets you prop up the iPad at different angles.

Using the iPad accessories, I got more work done on the tablet than on the notebook during my four-hour flight. It didn't help that the IdeaPad's fully charged battery conked out after just three hours. The iPad, on the other hand, still had six hours of juice left when I landed at LAX.

Still, there are some big drawbacks to flying solo with the iPad on business trips. Unlike the IdeaPad, it does not have ports for peripherals such as phone chargers or USB drives. And the current version does not have a camera for video chats, though the iPad 2 has front and rear cameras.

Nonetheless, I plan to leave my laptop at home the next time I hit the road. For my purposes—basic word processing, e-mail, Web surfing, and watching movies at the hotel—the tablet worked well and added less bulk to my bag. If you need to do more serious computing, grab the laptop instead.