5-in

Although you can use it folded shut, with one rectangular 3.5-in. screen facing out, it also pivots open to align that and a matching screen against each other to function as a single square display, 4.7 inch measured diagonally.

Smartphone stunts: Sprint introduces two-screen Echo, T-Mobile to give them away Rob Pegoraro 2011

Measuring 119.5 by 59.5 by 15.22 mm, it's among the thickest Windows Phone 7 phones, though its 3. 5-in. screen is the smallest.

Windows Phone 7: Promising, though not yet a clear game-changer 2010

Although you can use it folded shut, with one rectangular 3.5-in. screen facing out, it also pivots open to align that and a matching screen against each other to function as a single square display, 4.7 inch measured diagonally.

Smartphone stunts: Sprint introduces two-screen Echo, T-Mobile to give them away Rob Pegoraro 2011

Though specs are not yet available for the AT&T phone version, the Mini 3 some core specs, including its 3.5-in. touchscreen, 3-megapixel camera with flash, 3G support, and GPS navigation are expected to remain intact from the international version.

CES 2010: Dell, AT&T to launch their first Android phone for the U.S. 2010

Once unprecedented in size, the iPhone's 3.5-in. display is now dwarfed by the 3.7-inch displays of the Android-powered Motorola Droid and HTC Nexus One.

Six iPhone improvements we'd like to see tomorrow 2010

Once unprecedented in size, the iPhone's 3. 5-in. display is now dwarfed by the 3. 7-inch displays of the Android-powered Motorola Droid and HTC Nexus One.

Six iPhone improvements we'd like to see tomorrow 2010

Though specs are not yet available for the AT&T phone version, the Mini 3 some core specs, including its 3. 5-in. touchscreen, 3-megapixel camera with flash, 3G support, and GPS navigation are expected to remain intact from the international version.

CES 2010: Dell, AT&T to launch their first Android phone for the U.S. 2010

Measuring 119.5 by 59.5 by 15.22 mm, it's among the thickest Windows Phone 7 phones, though its 3.5-in. screen is the smallest.

Windows Phone 7: Promising, though not yet a clear game-changer 2010

Known as the Glisten, and available on AT&T for $375 with a two-year contract, the phone has an old-style Palm Treo look, with a relatively small 2. 5-in. screen and chiclette-style keyboard.

HP’s Palm acquisition could be good news for Palm owners 2010

Known as the Glisten, and available on AT&T for $375 with a two-year contract, the phone has an old-style Palm Treo look, with a relatively small 2.5-in. screen and chiclette-style keyboard.

HP’s Palm acquisition could be good news for Palm owners 2010