Well Trodden

Straight-line arrows send you over cliffs and into walls. Well Trodden learns the roads and paths you really travel, and when you set a TomTom waypoint, it marches a trail of dots along those paths to get you there. The more you play, the smarter the trail gets.
How it works
It learns as you play. While you walk, ride or swim, Well Trodden quietly saves your route. Crossings and shared roads join up into one network. Flight paths, teleports and hearthing are never recorded.
It routes along known ground. Set a waypoint (Ctrl+right-click the world map with TomTom) and the trail follows the paths you've walked, then takes the shortest hop to the waypoint itself.
Colors that mean something:
Green dots: a path you've walked before.
Orange dots: a straight line over ground you haven't walked yet, which may be blocked.
Blue dots (optional): a second, different route, shown only when a good one exists.
It favors your usual routes. Paths you walk often count as shorter, so the trail picks the roads you know best.
It stays put. The trail lasts as long as your waypoint does, even through /reload and logging out, and moves when you point TomTom somewhere new.
Minimap and world map. Dots march along your minimap, and the full route is drawn on the world map.
Settings
Show or hide the trail, and pause or resume learning.
How strongly to prefer known paths over shortcuts.
Ignore paths you've walked fewer than a set number of times.
Spacing between dots on the minimap and the world map.
Show every path you've learned on the world map.
Forget points near you (handy if you jumped down a cliff you can't climb back up), or erase a whole continent.
How to use
Install TomTom (required). Type /trodden to open the settings window, or use the minimap button or Options → AddOns → Well Trodden. /trodden help lists the other commands.
If the game ever hides your position from addons, for example in some instances, the trail pauses and picks up again as soon as it can.
Disclaimer
Well Trodden is one of a few addons I came up with to make quality of life easier for myself during the WoW Forever beta test. The ideas are my own, and I did not search for, look at, or use any other author's addons, code or artwork before making them. Any resemblance to existing addons is coincidental. Well Trodden requires TomTom, which you install separately. It uses TomTom's waypoints and map tools while running, but includes none of TomTom's files. Following a dotted trail is a common idea in guide addons; no code or artwork from any of them is used.
Made for WoW Forever. Released under the MIT license.