A text field is a single-line, fixed-height field, often with rounded corners, that automatically brings up a keyboard when the user taps it. Use a text field to request a small amount of information, such as an email address.
Show a hint in a text field to help communicate purpose. A text field can contain placeholder text—such as "Email" or "Password"—when there’s no other text in the field. Don’t use a separate label to describe a text field when placeholder text is sufficient.
Use secure text fields when appropriate. Always use a secure text field when your app asks for sensitive data, such as a password.
Tip For multiline or multistyle text entry, use a text view instead. See Text Views.
Show the appropriate keyboard type. iOS provides several different keyboard types, each designed to facilitate a different type of input. To streamline data entry, the keyboard displayed when editing a text field should be appropriate for the type of content in the field. If your app asks for an email address, for example, it should display the email address keyboard. For a complete list of available keyboard types, see the UIKeyboardType constant of UITextInputTraits.
Use images and buttons to provide clarity and functionality in text fields. You can display custom images in the left or right sides of a text field, or you can add a system-provided button, such as the Bookmarks button. In general, use the left end of a text field to indicate a field’s purpose and the right end to indicate the presence of additional features, such as bookmarking.
Display a Clear button in the right end of a text field when appropriate. When this element is present, tapping it clears the contents of the text field, eliminating the need to keep tapping the Delete key.
For developer guidance, see UITextField.