Revise text. Touch and hold the text to show the magnifying glass, then drag to position the insertion point.
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Select text. Tap the insertion point to display the selection options. Or double-tap a word to select it. Drag the grab points to select more or less text. In read-only documents, such as webpages, touch and hold to select a word.
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You can cut, copy, or paste over selected text. With some apps, you can also get bold, italic, or underlined text (tap B/I/U); get the definition of a word; or have iPhone suggest an alternative. Tap to see all the options.
Undo the last edit. Shake iPhone, then tap Undo.