A:AnswerThis TV does not have Chromecast/AirPlay built-in.
You can use the Apple - Lightning Digital A/V Adapter - Model: MD826ZM/A to connect your iPhone to this TV via HDMI.
A:AnswerAntenna required depends on local over the air broadcast channels. How far are you from transmitters, what is the terrain between you and transmission towers. If you are in a more urban situation you may get by with "rabbit ears" or similar, other may require a higher gain antenna on a 20 - 30 foot mast. I would consult with your local BestBuy dealer.
A:AnswerYou could try to do a Factory Reset, go Home > Settings > Device & Software > Reset to Factory Defaults.
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