These two commands first save the grep results to a temporary file and then populate Vim's quickfix list with the contents.

$ grep FooBar -irn ./src/app > /tmp/quickfix
$ vim -q /tmp/quickfix

The -i makes the search case insensitive, the -r performs a recursive search on all descendent directories, and the -n includes line numbers in the grep output. Those line numbers are important for Vim's quickfix list.

Once in Vim, use :cn to navigate to the next item in the quickfix list.

See also: