As with any video files recorded to a microSD card, you will need to view the .MP4 video files on a computer.
MicroSD cards come with an SD card adapter. Some computers have an SD card reader attached, but if yours does not, you will need to purchase an SD card reader for your computer to import and view the files.
When you open the video files on your computer, they will be contained in the “DCIM” folder on your microSD card.
The Gallery App on the Base is scheduled to be released in April 2018 so you can view the video files directly from your Base!