I'd like to insert perfect arrows (the sort you can make using Inkscape: straight, symmetric tips, of customizable width and length, etc.) into images in GIMP. At the moment the closest thing to this I can do is by holding down "shift" whilst using the PaintBrush tool which just creates straight lines (with no arrowheads).
GIMP features no ready "shapes" tools, or the ability to easily create arrows. You have to draw then manually - either zooming in the head region and using click_shift to raw two straight lines for the head - or using the paths tool to start with, manually putting two segments to the head, and selecting "edit->stroke" for the whole path.
The advantage of the second approach is being able to fine tune the arrow before the stroke or undo/adjust/stroke again.
Depending on the workflow, you could draw a nice, steady arrow in a separate image, then copy it and
edit->paste as new->brush - then you'd have a nice arrow stamp, with customizable size and angle to use with the brush tool.
There is a plugin:
arrow.scm and save it to
/home/username/.gimp-2.8/scripts (on a Linux system).
cd ~/.gimp-2.8/scripts wget https://web.archive.org/web/20160708211721/http://registry.gimp.org/files/arrow.scm
Check your version numbers, naturally. Next time you start up Gimp, you should see an Arrow option under the Tools menu.
Find out more about how to use it on maketecheasier.com.