We had a DVD player in the minivan but it eventually broke, not to mention we had problems with it (who has a DVD anyway) and couldn't watch Netflix on it (although it had an HDMI port, there were copy protection circuits preventing us from playing Netflix!). Currently the best option is to install an iPad with shows/movies preinstalled. The kids love it and it's very stable even when the kids play with it.
Flexible Arm Tablet Holder, Lamicall Gooseneck Tablet Stand: Clip Mount for iPad Mini Pro Air, Switch, Galaxy Tabs, and More 4.7-10.5" Devices - Gray
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Headrest Moonooda Universal Backseat Compatible
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π Universal Car Headrest Tablet Mount Holder - Compatible with iPad Pro 12.9/11, Phones/Tablets/Switch 4.7"-12.9" - Adjustable Headrest Posts Width 5.2in-5.7in - Sleek Black Design
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Innovative Car Tablet Headrest Holder: Adjustable Mount for iPad Pro/Air/Mini, Samsung Tablet, Fire Tablets, Phones (5"-13") - Black
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