A:Answer MyBook is designed for backups so is separately powered and more reliable, Element is designed for portability, so is smaller and lighter.
The WD backup software is downloaded separately from WD website and easy to use, but limited in functionality.
My drive was formatted exFAT from the factory, exFAT is supported by Android but you will need an adapter to connect to the phone directly (MyBook cable does not come with a USB C connector). I would not recommend the MyBook for use with phone or tablet because the drive has to also be plugged into the wall for power.
In the year 2021, 8TB is enough for most home users unless you are storing large archives of high definition video.