Re: file system access
FWIW I use an editor called Textastic. It has a builtin webdav server and it’s a 10 line bash script to ‘git archive’ any git repo over to it.
It’s not really 2 way (it might be possible, haven’t checked) but I use it as I would use a printout before: just to review and annotate code in detail. Can always email it back when annotated. Also has a ssh mode, haven’t used it.
Very nice editor with this clever widget to enter programming symbols quicker than with keyboard (iPhone version is keyboard only :-(