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.
10.5" Tablet Apple iPad Air 2019, 256 GB, Wi-Fi, iOS, silver
11 Review
Macally Phone or Tablet Holder for Mic Stand - Perfect for Music Stands and Boom Poles π± - 360Β° Rotating iPad Music Stand with C Clamp and Quick Release - Fits Devices 3.5β to 8β Wide
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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
10 Review
LISEN Headrest Compatible Smartphones 4 33In 8 66In
9 Review