Massive Improvements have been deployed to the GeoPDF export.  
A geospatial PDF contains information that is required to georeference location data for your exported map to work with several third party apps (i.e. Avenza Maps).
For details and step, check out the Layer Export Tool.

Improvements

  • Includes complex symbology
  • Includes labels
  • Symbols are not printed that are not visible at that scale when exported.  
  • You can export different Page Sizes
  • Within certain applications, i.e. Adobe, you can toggle layers on and off

Limitations

  • Some AGOL and Portal symbols do not come through, many still do
  • Most Imagery layers do not work, however, some imagery basemaps (from the selector at the top of the layers menu) do export
  • For larger extents, when zooming in some symbology will become fuzzy