Sales of PDAs continued a steep decline in the second quarter as struggling vendors shipped 719,000 units worldwide, down from 1.26 million last year, according to a market research report released Wednesday. The results mark a 43.5 percent decline, a drop so large that Dell recently decided to stop selling its Axim handset and leave the market segment to its competitors, according to IDC.

And with no sign of better sales on the horizon, remaining vendors like Palm face mounting pressure to justify remaining in the market, said IDC analyst Ramon Llamas.