The Palm Centro is actually a well-built device. There are very minimal creaks, and you have to be really abusing it to get them. The Centro is hefty, but not heavy. It feels very solid and nicely weighted in your hand. The size is phenomenal, easily slipping into a pocket or purse. The screen is well lit in general, though not very readable in direct sunlight.
The front of the device is slightly unbalanced, with a 4-5mm gap between the screen and the d-pad. Had they used that area to put in a larger QWERTY keyboard, the device would have been a lot better. The QWERTY keyboard on the Palm Centro is one of the biggest pitfalls. It's entirely too small and cramped, and the keys are made of what feels like a hardened gel. The keyboard does have good tactile feedback, but I found it completely unusable. It doesn't help that the Centro does not feature handwriting recognition or an onscreen keyboard that I could find.
The bottom of the Centro is where you'll find Palm's proprietary ports for data and charging. A nice touch, however, is that there is an adapter included in the box to enable the Centro to accept the standard Sprint charger.
The phone sports IrDA connections, which I'm sure is useful to someone, somewhere. Right below the IrDA port is the microSD card slot, though you must remove the battery door to gain access to the memory card. On the left side of the phone is the volume rocker, as well as a shortcut key for the voice activated dialing and voice commands.
Above the QWERTY keyboard are the d-pad and shortcut keys. The d-pad is actually an elongated chrome ring. Pressing up, left, and right are all very nice and provide good feedback. However, I found that the ‘down' direction was very soft, and had to press it numerous times before it actually felt like I was getting it right. The shortcut keys are, clockwise from top left: phone, home, messages, and calendar. There is no 'back' button on the Centro, making navigation slightly difficult.