It’s a good idea to test your application using VoiceOver, because it allows you to experience the application in the same way that VoiceOver users will experience it. Using VoiceOver to run your application can expose problem areas, for example, confusing labels, unhelpful hints, and unreachable elements that make your application less accessible.

VoiceOver is a sophisticated application that provides many powerful features to users with disabilities. For example, VoiceOver users can use an invisible dial, known as the rotor control, to change the results of some gestures on the fly. Although you don’t need to become an expert VoiceOver user to test your application with it, you do need to know a handful of basic gestures. This section describes how to activate VoiceOver and use it to run your application.

First, go to Settings > General > Accessibility > VoiceOver and tap the switch control to turn VoiceOver on. If you provide hints for any accessible elements in your application, check to make sure the Speak Hints switch is on (it is on by default). Before leaving VoiceOver settings, make sure the Speaking Rate slider is adjusted to an appropriate value.

After you’ve turned VoiceOver on, you’ll notice that many familiar gestures have different effects. For example, a single tap causes VoiceOver to speak the selected item and a double tap activates the selected item. There are also a couple of new gestures you should learn to make testing your application with VoiceOver easier. The gestures you’re most likely to need for testing are listed below:

  • Drag over the screen. Select and speak each item as you touch it.
  • Tap. Speak the selected item.
  • Two-finger tap. Stop speaking the current item.
  • Flick right or left. Select the next or previous item.
  • Double tap. Activate the selected item.
  • Two-finger flick up. Read all accessible items from the top of the screen.
  • Two-finger flick down. Read all accessible items from the current position.

There are also a few tasks you might need to perform. For example:

  • Enter text on the keyboard. Flick left or right to select the desired key, then double-tap to enter the character. Alternatively, you can drag your finger over the keyboard until the desired key is selected. Then, while holding the selected key with one finger, tap the screen with another finger to enter the character.Flick up or down to move the insertion point forward or backward in the text.
  • Scroll a list or area of the screen. Flick up or down with three fingers.
  • Adjust a slider. Flick up or down (with a single finger) to increase or decrease the setting.
  • Unlock iPhone. Select the Unlock switch, then double-tap the screen.

When an element is selected, VoiceOver draws a black rectangle around it (similar to the shaded rectangle Accessibility Inspector draws), which is called the VoiceOver cursor. While you’re testing your application you can use the VoiceOver cursor as another way to make sure elements are being selected as you expect.

To simulate the experience a visually impaired user might have with your application, you can run it with the VoiceOver Screen Curtain in place. When you activate the Screen Curtain, VoiceOver turns the device display off. Testing with the display turned off obliges you to rely on the information VoiceOver speaks and removes the temptation to use your application as a sighted user would. To turn off the display while you use VoiceOver, triple-tap the screen with three fingers. To turn the display back on, perform the same gesture again.