When there's an incoming call on an iPhone, there are several different options that Apple provides beyond simply answering or letting it ring, and among these is the ability to reply with a text message. This is a great way to make a busy day a little easier to manage. The great thing about a text is that it’s an immediate response but doesn’t open the door for a long conversation when time is short.
The iPhone takes calls and messages seriously. For such a simple utility, the Phone app is, in a way, the most important app of them all – the iPhone’s reason to exist. It’s a perfect example of Apple’s design guidelines, representing the look and feel of a standard touch-tone keypad with a few extras that hide its advanced features. The dialer is only half of the story, however, and the way incoming calls are handled is also interesting.
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Apple has given iPhone users the ability to respond to an incoming phone call with a text message right from the lock screen. It's quite simple since a small white Message button appears above the larger green Accept button at the bottom-right of the screen. Tapping Message reveals a menu with four choices. Any of the three predefined messages, 'Sorry, I can't talk right now.', 'I'm on my way.', or 'Can I call you later?' can be tapped. Alternatively, a custom message can also be entered by tapping 'Custom…', quickly sending a text to the caller.
It's also possible to customize the iPhone's predefined text messages to use phrases that might be more useful or which sound more natural to the user. For example, 'Sorry I'm running late!', 'Please go ahead, I'll be there soon.', and 'Please text instead, can't talk now' might
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