The phone portion of my Palm Centro has been slowly dying for the past few months. The signal strength varies wildly over time. Occasionally I'll look at the Centro's status display and see the full 4 bars indicating a strong signal. Minutes later at the same location it may show a single bar or worse yet, the dread "SOS Service Only" message. A visit to Google indicates that this is a very common problem with Centros.
So much for my attempt to combine PDA and phone functionality into a single device. I had such high hopes for the Centro. Having been a Palm PDA user since I got the original Pilot as part of a special employee purchase back when I worked for U.S. Robotics, I've grown to depend on my PDA heavily. Palm PDAs provided the ideal combination of application support and built-in features. If only their phone capability worked as well as the rest of the device.
I've been doing a bit of research and so far I don't see a suitable replacement device, at least not among the subset of devices available from my cellular provider. The iPhone comes closest but I'm too cheap to want to be saddled with a $30 per month data plan when a little planning can make it completely unnecessary. The iPhone doesn't make any sense without the data plan. Many of the other smart phones suffer from poor battery life, poor signal quality, crashes, or insufficient application support.
For the time being I've switched back to my old Motorola Razr phone which despite its age has much better signal strength and battery life than the Centro did when it was new. I'm using the Centro without a SIM card as a standalone PDA device.
I'm considering the Motorola Q Windows Mobile device. I can find Windows Mobile equivalents for all the applications I've come to depend upon (contact management, calendar, to-do list, memos/notes, database, and secure password storage). I've got a few months before I'm eligible for a reduced cost equipment upgrade. I'm hoping a better option presents itself between now and then as the prospect of switching to a Windows Mobile device doesn't thrill me.