vi: how can I jump to end of file with a new line appended?
What about Go, successively? ;-)
An alternative with command line:
:$put _
If you want to understand that, you can also read this answer on registers
One way to do this is to create a macro and place it in your .vimrc file.
map , GA<enter>
This will map the comma key. When pressed, vi will go to the end of the file, go to the end of that line and create a new blank line. This will also leave you in insert / edit mode.