Hema 4WD Maps has great coverage for Madigan.
From other place like the Vic high country, they can be poor for detail.
Hema really covers most of Australia reasonably well.
Mapout has all the Madigan camps and track marked, it a cheap iphone compatible app (used to be free) about $5 I think.
Very good used in conjunction with my Hema maps, as well as old Garmin nav on the dash.
I use them all in conjunction with each other, Mapout zoomed in shows great detail, contour lines, places of interest, but zoomed out they disappear, so you have to juggle it if using it alone.
My old Garmin dash nav I usually leave zoomed out to give relative info for nearby points, like a lake, mountain, and use it to give overall picture of surroundings I can relate to other mapping.
Mapout is what I use to record travels (on the iphone), Hema on an old ipad with glonass module I use just like a paper map, just follow progress on screen map.
Mapout and / or Hema on an ipad mini or regular size, on a dash mount will get you through madigan and all approaches no probs.