Design-wise the SDA is a bar-phone (4.5"x1.8"x0.7") but unlike its predecessors it's got a bigger, brighter and more color saturated display (2.2" TFT with 65,536 colors, 240x320 pixels) which is easy to look at both in and outdoors. The shortcut keys that enable you to access some of the key features directly from the keypad, instead of looking for them in the menu, are a plus. The weight of the phone (3.7 oz) allows it to be carried with no effort in hand or in the pocket. And to top it off are the stylish grey color and the smooth edges that give the SDA a rather pleasant futuristic look.
As far as the keypad goes, the SDA has the standard 12 keys which are reduced to the minimal possible size in order for the phone to accommodate the enlarged screen. The navigation through the menus is done by using a 5 way (left, right, up, down and push) joystick key positioned between the call and the hang up buttons. T-Mobile has made sure that the phone has the t-zones button right on the keyboard for easy access to their home page where the company offers content for its customers (wallpapers, ring tones, caller tunes, etc.). Pause/play, fast forward and rewind buttons are lined sideways next to the t-zones button for easy access to the media content stored on the phone. Right under the display and smallest in size are the context buttons, which functionalities vary depending on the screen that you are looking at. Besides the buttons on the front of the phone, there are 4 more buttons, and those are the power button (on the top), next to the infrared port, the comm manager button and the volume dual button (on the left side), and the camera key (on the right side), which allows you to bring up the camera within a second when you need it.
In general the buttons are very well responsive and comfortable to use, although the small size of them could eventually be a problem for people with larger fingers. On the bottom of the device are located the 2.5 mm jack as well the portable USB port for the power adapter and the sync cable. On the back of the phone is located the 1.3 Mega Pixels camera with a self portrait mirror.