The SGH-ZX20 measures 3.5 by 1.9 by 1.0 inches and weighs in at 3.9 ounces. As a result, it's easily portable and will fit in smaller pockets. It also benefits from a solid construction, and it feels comfortable in the hand. An external antenna adds a bit more girth, but it doesn't feel flimsy. Front and center is the external display. Though it's big for the phone's size (1 inch diagonally), we were disappointed that it was monochrome only. It shows the date, the time, battery life, and signal strength, but it doesn't support photo caller ID. Though you can adjust the contrast or personalize the screen with a greeting or a rudimentary image, it's just below our expectation for a megapixel camera phone.
Immediately above the display is a small flash, while the camera lens sits in the middle of the hinge. In a nice touch, the lens swivels 180 degrees, enabling you to take self-portraits or shots of objects away from you. On the right spine is a button for changing the ringer profile and the covered MicroSD card slot. A volume rocker and a covered headset jack sit on the right spine, while the bottom end houses the charger port. We were hoping, however, for an external camera shutter.
Inside the phone is the 262,000-color TFT display. As previously mentioned, it's smaller (1.75 inches diagonally) than many other 3G phones, and at 176x220 pixels, it also has a lower resolution. While it's perfectly fine for scrolling through menus, playing games, and taking photos, it won't do justice to the streaming video. You can change the backlighting time, the brightness, and the font size and color. Yet like most Samsung displays, it's difficult to see in direct light.
The navigation controls and the keypad buttons take cues from the Samsung SGH-ZX10 as well. The four-way toggle is a bit small, and the OK button in its center instead acts as a Web browser shortcut when in standby mode rather than opening the main menu. We liked, however, that the toggle can be set to give one-touch access to four user-defined functions. Immediately above the toggle are two thin controls that activate the camera and open a secondary shortcut menu. While the keys were user-friendly, their placement above the two soft keys was confusing because we kept pressing them to activate the command on the screen. On the other hand, the actual soft keys are large, as are the Talk and End/power buttons and also the dedicated Clear control. The backlit keypad buttons are large, easy to read, and well spaced, but they're flush with the surface of the phone, which made dialing by feel difficult. The Samsung SGH-ZX20's phone book holds a hefty 1,000 contacts, while the SIM card holds an additional 250 names. Each entry holds five phone numbers, two e-mail addresses, a Web address, a birthday, a job title and company, a nickname, and notes. You can organize callers into groups and pair them with one of 5 polyphonic (64-chord) or 10 MP3 ring tones. You can also assign photos to a contact, but as previously mentioned, they won't appear on the external display. Other features include a vibrate mode, text and multimedia messaging, an alarm clock, a daily and weekly calendar with an event scheduler and a task list, a calculator, a unit converter, a world clock, and a speakerphone. Instant messaging is on board as well with options for AOL, MSN, Yahoo, and ICQ, and in an improvement over the Samsung SGH-ZX10, there's full Bluetooth 2.0.
As we said earlier, the SGH-ZX20 follows the LG CU500 as Cingular's second HSDPA phone. A step above the 3G UMTS network on the SGH-ZX10, HSDPA is a 3.5G technology that essentially brings wireless broadband data speeds to a cell phone. Cingular is promising speeds of 400Kbps to 700Kbps for its HSDPA network, which allows for steaming video and quick downloads. The ZX20 supports Cingular Video, and its full assortment of programming that includes news clips, weather reports, and sports recaps.