Convert what ever video file to a compatible MP4 file that works on most devices.

video2mp4.sh

#!/usr/bin/env bash

if [ "$1" == "-h" -o "$1" == "--help" -o "$#" == "0" ]
then
    echo "Convert what ever video file to a compatible MP4 file"
    echo "that works on most devices."
    echo
    echo "Usage: video2mp4.sh [FILE]"
    exit
fi

FILE="$1"
ffmpeg -i "${FILE}" \
  -c:v libx264 \
  -crf 24 \
  -pix_fmt yuv420p \
  -tune film \
  -c:a aac \
  -b:a 128k \
  -ar 44100 \
  -vol 300 \
  -strict -2 \
  -speed fastest \
  "${FILE%.*}-converted.mp4"
  

Another option is just use VLC > "Media" menu > "Convert / Save...".