Not everyone has the full use of their fingers, and that’s a problem when it comes to such common iPhone “gestures” as pinching and swiping the touchscreen.

The solution: the iPhone’s helpful “AssistiveTouch” feature, which lets you create a custom menu of multitouch gestures that you can perform with just a few taps, no pinching or swiping required. Indeed, once you’ve got AssistiveTouch up and running, you can do just about anything on your iPhone (or iPad, or iPod Touch) with a single fingertip, or even a stylus.

The "AssistiveTouch" menu lets you turn up the volume on your iPhone, lock the screen, and more with a single fingertip.

To turn on AssistiveTouch, go to the main iPhone home page and tap Settings, General, and Accessibility. Scroll down to the bottom of the page, tap the AssistiveTouch option, and tap the “On” switch at the top of the following screen.

Once that’s done, you should see a translucent square in the bottom corner of the display; tap it, and a menu with four icons—Gestures, Favorites, Device, and Home—should appear.

Tap the “Device” icon, and you’ll see a series of six options: Rotate Screen, Lock Screen, Volume Up, Volume Down, Shake, and Unmute.

Tap the Volume Up icon, for example, and you’ll crank the iPhone’s volume up a notch, all without having to press the stubby (and stubborn) aluminum button on the iPhone’s left edge.

Or, if you’re using an app that requires a shake of the iPhone itself (like the iPhone’s optional “shake to undo” feature), you can tap “Shake” in the AssistiveTouch menu rather than shaking the actual handset.

Next, we have “Gestures,” which lets you try two-, three-, four-, and even five-finger gestures with just a single fingertip—handy for those new iPad gestures that let you (for example) switch from one app to another with a four-finger swipe.

The AssistiveTouch feature can help with those tricky new iPad gestures, like the four-finger swipe for the multitasking bar.

The “Favorites” icon is where you’ll find the famous iPhone “pinch” gesture, most often used for zooming in on a web page or a photo. Tap “Pinch,” and a pair of blue, fingertip-sized dots connected by a thin bar will appear; just tap and pull with one finger to “pinch” the screen.

Even better, though, is the option to create your own gestures. Tap the “+” sign to “record” any gesture you want—say, a downward swipe. Now, whenever you want to scroll up on a lengthy web page, just call up the AssistiveTouch menu, tap “Favorites,” and then the icon for your new “swipe down” gesture. Now tap the screen, and it’ll obediently scroll down just as if you’d swiped it.

Last but not least is the “Home” icon, which does what it says: it sends you straight to the iPhone’s home screen. You can also double-tap the Home icon to reveal the iPhone’s multitasking bar at the bottom of the page.

Got more iPhone/iPad questions, or a tip to share? Post ‘em in the comments below.