On Monday, Apple updated its PowerBook line with faster speeds, new features, and lower prices. One of these new features is a “scrolling trackpad”—whereas all trackpads let you move the mouse cursor by dragging a single finger across the pad (and “click the mouse” by tapping the pad), the new trackpad design also lets you scroll through documents (or pan within windows) by dragging two fingers across the pad.
Unfortunately for users of older PowerBooks, this functionality isn’t provided via a simple software update; it’s actually a feature of new trackpad hardware. However, other PowerBook (and iBook) owners can gain similar functionality by installing a previous Mac Gem, the $15 SideTrack 1.1 ( ).
SideTrack is a replacement trackpad driver for Mac OS X. When installed on a PowerBook or iBook, it lets you designate a portion of your PowerBook or iBook trackpad as a “scrollpad”—simply drag your finger up and down (or left and right) to scroll through windows. In addition, you can modify your trackpad so that pressing the trackpad button and tapping on the trackpad itself can do two different things; for example, one can be a standard click and the other a control-click. It also lets you assign the corners of the trackpad to different functions. Here's a full list of the features provided by SideTrack:
- Use the left or right edge of the trackpad for scrolling up/down.
- Use the top or bottom edge of the trackpad for scrolling left/right.
- Use the trackpad button as a standard mouse click or a control/right-click.
- Map a “tap” on the trackpad to a standard mouse click, a click-drag, or a control/right-click.
- Map the corners of the trackpad to either particular mouse buttons or keyboard shortcuts—tap the corner to execute the action. (These corner settings can be system-wide or per-application.)
- Adjust standard trackpad preferences: tracking speed, double-click speed, etc.
- Automatically move the mouse cursor to the default button (OK, Print, Cancel, etc.) in dialogs.
- Continue mouse movement when your finger reaches the edge of the trackpad—no more “drag - hit edge - lift finger - move back to other side of trackpad - drag again” motion when you're trying to move the cursor all the way across the screen.
- Enable and configure impressive trackpad calibration and input filtering options that help prevent accidental actions.
As I noted in the original review, I’ve been using various beta and release version of SideTrack for the past year, and now using a laptop without it feels limiting. I personally have SideTrack set to scroll up/down using the right side of the trackpad and scroll left/right using the top edge. I’ve also got the lower-right corner of the trackpad set to control/right-click, the upper-right set to command-W (for closing windows), the upper-left set to command-click (great for opening links in Safari in new tabs), and the lower-left set to shift-command-Right Arrow (for switching between tabs in Safari).
Even if you don’t use SideTrack’s button/scrolling functionality, its features for customizing the speed and sensitivity of your PowerBook or iBook trackpad are significant improvements over the options available in Mac OS X. It even offers a “Redmond switcher” trackpad acceleration setting that emulates the trackpad profile of many Windows laptops—helpful for new Mac users switching from Windows laptops.
SideTrack is a kernel extension, so make sure to read the documentation provided before you install it. But once you do, you’ll likely never go back to the standard trackpad functionality.
[Note: At this time, I don’t know how well, or even if, SideTrack works with the new PowerBook trackpad hardware. Hopefully it will be compatible, because despite their nifty scrolling feature, the new trackpads are still missing a lot of functionality provided by SideTrack.]