Smart phones -- cellphones with a big screen, a keyboard and the ability to run add-on programs -- are not necessarily phones to the people who use them. Their versatility allows them to impersonate the other handheld devices you might otherwise carry around; in reality, any given smart phone may be a datebook, a Web browser or an MP3 player that happens to place the occasional call.
Then again, it's hard to find a device equally competent at all of these possible uses, as a trial of four recent models showed. These four gadgets -- Nokia's E62, Palm's Treo 680, Research in Motion's BlackBerry Pearl and T-Mobile's Dash -- bear a superficial resemblance. All can fit in a pocket, though the wide E62 and the relatively thick 680 do so less gracefully than the other two. The other devices all gum up phone functions by forcing you to navigate though on-screen menus, though the BlackBerry was less compromised than the others. Its key-guard button is right on the top, and its silent-mode command is only a couple of button presses away.
