With it's slim, curved look, the Cowon S9 mp3 player has received a lot of hype, and it is well deserved. The curved edges make it fit well and feel great in the palm of your hand. Even though it is made of plastic, it still has a nice solid feel that you wouldn't expect, and the touch screen is made of glass, which is a nice touch.
The interface of the touch screen is very nice and intuitive, and for people who prefer tactile use, there are buttons for all of the major functions, like volume, forward/reverse, pause/play, and hold. The buttons are extremely useful if you use your mp3 player while running or working out and keep it in your pocket. The one thing I must say is that the power button is sort of in an awkward place, being adjacent to the headphone jack, making it extremely difficult to access with headphones plugged in.
The library browser works great to quickly navigate your music selection, and you have the ability to zoom in on just about all of the screens. The user community has come up with several nice modifications to the default user-interface, but unfortunately none of these come with the base product. They are easily downloaded though, so I don't consider that too big of a hassle.
The playback interface lets you take a look at file info, such as bit rate and file type, and there is also a display of cover art, and it is all easily navigated. The thing I really enjoyed is the bookmarking feature that will remember where you were at in a file, and will also pull up an entire playlist for you. People who are fans of the coverflow feature on other mp3 players will also find that on the Cowon S9. However, you are currently unable to make dynamic playlists, just one favorites list.
And now we come to the AMOLED screen. It's fantastic! The colors are sharp and contrast beautifully. The device uses a built-in accelerometer to flip or rotate your screen when utilizing music, movies, text, and photos. If I had to go with the best feature of this device, it would be the AMOLED screen.
The radio tuner isn't great, but the sound quality is not bad. The radio user-interface is ok, too, but a little sluggish.
Quality of the Bluetooth audio is superb, and comes with all of the sound enhancement capabilities you expect from Bluetooth. The battery life is also excellent. It can run for hours on end without hardly losing any power.
Overall, you definitely get a lot of bang for your buck with the Cowon S9 mp3 player. I highly recommend it to people who are looking for a touch screen device.