First off what is a VOB file. VOB is the container format for DVD that stores audio, video, subtitles, menu info, etc. Apple products do not really provide support for VOB format, so an "open VOB file on Mac" issue is always there. This format is based on the MPEG stream format, but with some limitations and specifications added.
In order to play VOB on Mac you will definitely need a VOB Player Mac app. One of the best and most reliable solutions is Elmedia Player. A lot of users prefer Elmedia Player because it can play most of the video formats and audio too. Not only is it a great VOB player for Mac, but it also allows playing formats that QuickTime fails to play natively, and this is most MPEG/VOB, ASF/WMA/WMV, VIVO, QT/MOV/MP4, AVI, Ogg/OGM etc.
It is very easy to watch VOB videos on your Mac. Use Elmedia Player to play VOB files on Mac.
1. Download Elmedia
1.1 Get Elmedia Video Player app by downloading from this website and enjoy being able to open all video formats on your MacOS device.
1.2. Install Elmedia Player by downloading it from the Mac App Store and then open it to enjoy its benefits.
2. Enjoy your videos
Add and play VOB files in Elmedia Player. There are several ways to do that:
Drop VOB files on the opened player window or onto its icon in the dock.
Find and right-click VOB video in Finder and use "Open With" option from the menu. Then choose Elmedia Player to open the video.
Choose "File" and then "Open" in Elmedia Main menu.
3. Watch multiple video formats with versatile settings
It's not just VOB files you can open in Elmedia. It also supports way more file types: FLV, SWF, MP4, MKV, MOV, AVI, WMV, etc.