Apple gives an option to iPhone users to silence all calls from unknown callers. Go to Settings > Phone > Silence Unknown Callers to enable this option.
It can be tough to place the text cursor precisely where you want it. To fix this, just press and hold the space bar until the characters on the keyboard disappear. You can now utilise the space as a trackpad and move the cursor as you like it.
Users of iMessage can send messages with special effects. Before sending any iMessage, just press and hold the send key to select the effect you want to share with the message.
You can hear the person on the other side of the phone when on mute, but they can't hear you. When you put the call on hold, neither of the participants can hear the other one.
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