The iPhone 4S Special Use Keys
The virtual keyboard of the iPhone 4S contains five keys that don’t actually type a character. Along with using the Shift key to type capital letters, you can press a key to activate Siri and start dictating instead of typing.
The special-use keys and what they do:
Shift key: Switches between uppercase and lowercase letters if you’re using the alphabetical keyboard. If you’re using keyboards that show only numbers and symbols, the traditional shift key is replaced by a key labeled #+= or 123. Pressing that key toggles between keyboards that have just symbols and numbers.
To turn on caps lock mode and type in all caps, you first need to enable caps lock. You do that by tapping the Settings icon, then tapping General, and then tapping Keyboard. Tap the Enable Caps Lock item to turn it on. After the caps lock setting is enabled (it’s disabled by default), you double-tap the shift key to turn on caps lock. (The shift key turns blue when caps lock is on.) Tap the shift key again to turn off caps lock. To disable caps lock completely, just reverse the process by turning off the Enable Caps Lock setting (tap Settings, General, Keyboard).
Toggle key: Switches between the different keyboard layouts.
International keyboard key: Shows up only if you’ve turned on an international keyboard.
Delete key: Erases the character immediately to the left of the cursor.
If you hold down the delete key for a few seconds, it begins erasing entire words rather than individual characters.
Return key: Moves the cursor to the beginning of the next line.
Microphone/Siri key: Tapping this key, which appears in apps such as Notes and Messages, lets you use Siri to dictate your words.