What Is This Rotor Thing?
The VoiceOver rotor is perhaps the most difficult aspect of VoiceOver to get used to because it is not a concept used in other screen readers. It is basically a way to use the same two gestures--an up and down swipe with one finger--to perform multiple tasks. That is, an up or down swipe will do the action set in the rotor, and the rotor can be set at any point. The rotor is used for reviewing text by word or character, changing the typing mode, adjusting VoiceOver's volume, changing options, accessing handwriting or braille screen input, editing text, and spellchecking. It can be used to move by many different elements, such as link, heading, form control, and the like. At any point, the rotor options will only be those that are valid for the current context. For instance, many web pages will allow navigation by heading, link, landmark, and more, while a page in settings may offer only headings. Character and word navigation are always offered, as are any options you enable in VoiceOver's rotor settings.
To change the rotor setting, place two fingers on the screen and turn them. The important thing is that each finger moves in the opposite direction as the other finger, but at the same time. This means that, if you are having trouble "turning the rotor" with one hand, you can use one finger from each hand and move them in opposite directions. You will know when you are successful when you hear a scratching sound and VoiceOver announces the new rotor setting.
Once you have moved to the desired setting, swipe up or down with one finger to perform the selected action. This is where things can get confusing. When set to most settings, this swiping motion will move by the rotor item. For instance, selecting "words" will make the upward swipe move back one word, and the downward swipe move forward a word. Some rotor items, though, are menus of options. These items include edit and typing mode, both only available when you are editing a text field, or the actions available on some elements such as emails. Swiping up or down will, instead of moving by any amount through the text of what you are focused on, move up or down one item in the menu. When you hear the item you want, double tap.
Finally, the up and down flicking gestures are also used to control things like table indexes or sliders. When you are on such an element--such as the volume control in the Music app or the Speech Rate adjuster in VoiceOver's settings--swiping will move by a certain amount, such as ten percent. You will also find that a new item appears in the rotor, called "adjust value". When you are on an element that requires the use of the up/down swipe, this rotor item is selected automatically. Once you leave the adjustable element, your previous rotor setting is selected and the "adjust value" item disappears.
Sometimes, you will hear the scratching sound that indicates the rotor has turned, but the setting will not change. In this case, just repeat the turning gesture, moving your fingers a bit more than your previous try. In addition, rotor items may seem to be skipped. This just means you turned the rotor a bit too enthusiastically and moved by two rotor items instead of one.
The above is likely still rather confusing, so let's step through some practical examples.
Spell an App Name
Go to your home screen and touch an app. VoiceOver will speak the app's name, but what if you want to know how that name is spelled? Simply turn the rotor until you hear "characters", then swipe down. VoiceOver will speak the next character of the name with each swipe. It will say the letters in reverse order if you swipe up instead of down. If you rotor again, you should land on "words". Now, swiping up and down will cause VoiceOver to speak each word in the app's name, instead of each character.
When you touched the app we're using, you may have heard VoiceOver announce, "actions available". As you turn the rotor, notice that the "actions" item is now an available rotor setting. When you are on this item, you can swipe up or down to move through the actions available. For apps, this is usually just the option to begin editing your home screen.
Actions are used a lot in iOS and iPadOS. Just some of the places you'll find actions are: emails, files and folders in the Files app, app icons, widgets, conversations and individual messages in the Messages app, voicemails and recent calls in the Phone app, and notifications. There are a lot more areas, so always listen fo the announcement of "actions available" as you use your device. When you hear it, swipe up or down with one finger to move through the actions, and double tap when you hear the one you want.
Open a page in Safari. Once it loads, turn the rotor. You'll find the usual characters, words, and other options, but you'll also find more. You're now on a webpage, so VoiceOver knows it can navigate by extra things here. You can, for instance, rotor to "links". Now, as you swipe up and down, you'll move from link to link on the page. You can do this for headings, edit fields, and a lot of other element types. If you return to your home screen, though, you'll find that all these HTML navigation options are gone from the rotor.
Customizing the Rotor
You can go to VoiceOver's settings, then into Rotor, to customize where various rotor items appear, or whether they show up at all. Use the draggable item next to each item to move it around, or double tap an item that is "selected" to never have it appear in the rotor at all.
There's one important thing to note here. If you turn on handwriting or braille screen input, these will show up in the rotor wherever you place them, like anything else. However, you can force either of these items to always be one clockwise rotor twist away, instead of you having to turn the rotor a bunch to get to them. If you are a heavy braille screen input user, for instance, saving yourself two, or three, or five rotor turns each time you want to braille something can be extremely helpful.
To set this up, you need only move braille screen input or handwriting to the very top of the list, and make sure it's selected. If one of these two items appears first in the list of possible rotor items, it will always be one clockwise turn of the rotor away, regardless of which rotor item you were on before.