From Ars Technica:
There are two kinds of people in the world—those who believe in the power of the PDA and those who don't—and the first group is shrinking faster than a cotton shirt in an industrial dryer. If you're the sort of person who won't part from a beloved Tungsten E until it is pried from your cold, dead fingers, now may be a good time to start stocking up on replacements. According a variety of new reports, the PDA market is drying up. In the year between the second quarter of 2006 and the second quarter of 2007, for instance, PDAs saw an astonishing 43.5 percent decrease in worldwide shipments, and no more than a million devices were sold in the quarter.
It’s definitely a sad time for PDAs. I remember five or six years ago, when I first started to look at the PDA market it seemed like there was plenty in store for the future. PDAs were getting smaller, packing in more features like high-resolution screens and wifi, and manufacturers like Palm and Sony were coming out with some very high quality, innovative and stylish designs. It all seemed to stagnate though. There’s been very little true innovation in PDA software (both operating systems and third party applications), and hardware manufacturers have been either re-using their existing designs or getting out of the business altogether. When I look at the iPhone today, that’s more or less the future I had thought was in store for big PDA manufactures like HP and Sony.
I guess I share the blame in a small way, though. I had a few small unreleased games and a web application for Windows Mobile I used to be involved with, and I pretty much forgot about them once I started programming for Mac OS X.