iPhone with Voiceover rotor control

The rotor control is an invisible dial that you can use to change the
results of up and down flick gestures when VoiceOver is turned on.
Operate a rotor:

Rotate two fingers on the iPhone screen to turn the dial to choose
between options.

The effect of the rotor depends on what youre doing. For example, if
youre reading text in an email you received, you can use the rotor to
switch between hearing text spoken word-by-word or character-by-
character when you flick up or down. If youre browsing a webpage, use
the rotor to choose whether you hear text word-by-word or character-by-
character, hear just the headers, hear just the links (all of them,
visited links, or links not yet visited), hear form elements, or hear
descriptions of images. In other words, you can use the rotor setting
to hear all the text, or to jump from one element to another of a
certain type, such as headers or links.

Rotor options depend on the context of what youre doing.
Reading text

Select and hear:

*

text character-by-character
*

text word-by-word

Browsing a webpage

Select and hear:

*

text character-by-character
*

text word-by-word
*

headers
*

all links
*

form elements
*

links visited
*

links not visited
*

images

Entering text

Move insertion point and hear:

*

text character-by-character
*

text word-by-word
*

auto-text

Using a control (such as the spinner used to set the time in Clock)

Select and hear:

*

value character-by-character
*

value word-by-word

Or, adjust the value of the control object.