Continued criticism by industry insiders didn't stop vendors from OQO to Lenovo and LG from showing off ultramobile PC products with range of innovative features at the International Consumer Electronics Show (CES), held in Las Vegas this week.

With many of the prototypes displayed due to hit the market later this year, UMPCs continue to be panned for their inconvenient keyboards, small screen sizes and poor battery life ever, since the first UMPC from OQO was introduced at CES in 2004.

OQO showed off a WiMax-capable OQO Model 2 UMPC, powered by Via Technologies' C7-M mobile processors and running Windows Vista OS. It comes with hard-drive or flash-based solid-state drive options, supports up to 1G byte of RAM, and has a sliding display that pops up to show a keyboard. Weighing around 1 pound (453 grams), prices start at US$1,299.

Eyes were locked on UMPC prototypes from companies including Lenovo and Founder at Intel 's booth. The Lenovo device includes the Linux OS from Chinese developer Red Flag Software, and boasts a 4.8-inch touchscreen, an onboard camera, and other features. The Founder Mini-Note features a 7-inch screen, a 60G-byte hard drive, Wi-Fi and Bluetooth wireless networking, and weighs around 800 grams.

Intel's prototypes are based on its Menlow platform, a code name given to a set of Intel chips for ultramobile PCs due out next year. Menlow will include a new low-power microprocessor, code-named Silverthorne, and a chipset code-named Poulsbo.

One prototype that may never ship is a slider UMPC displayed in LG's booth, also based on the Menlow platform. The device runs Windows Vista, comes with a 4.8-inch screen, 1G byte of memory, a 40G-byte hard disk drive, a touchscreen, Bluetooth, Wi-Fi and 3G HSDPA cellular data. A representative at the LG booth said the company had not decided whether to market the device, as it suffered from poor battery life and keyboard usage issues.

UMPCs create a design challenge by virtue of being a tweener -- neither a cell phone nor a laptop, said Phil McKinney , vice president and chief technology officer at HP's personal systems group. "The UMPCs -- OQO and those guys -- are trying to be too much on the small side, very heavy, not great battery life, they get hot in your hand too when you use it. But when you get north of 9-inch screens, you're getting pretty close to a laptop," McKinney said.

The IDG News Service is a Network World affiliate.