It works with Auto-Guide to provide even more capabilities like: visual mapping on-the-go - see your place in the field, leave marks in the field, select individual local base stations where multiple base stations are used, as well as log NMEA data.
Auto-Guide Companion is transferable between machines.

The main features of Auto-Guide companion include:

Mapping Features:

• Records path traveled to generate "Area Covered" maps
• Records field boundaries and calculates acreage
• Records individual points
• Data can be saved as Mapinfo Interchange Files (.mif) or ArcView Shape Files (Point, Path, or Boundaries)

Guidance Wayline Features:

• Recall the wayline currently used by Auto-Guide
• Create or change Waylines in the field
• Save multiple waylines for each field
• Share waylines between multiple machines in a field
• Beam waylines to other Pocket PCs, or save them on your Office PC
  Guidance Local Base Station Features:
• Select between multiple Local Base Stations
• Retrieve the current Base Station from the machine
• Add new Base Stations as simply as entering the Serial Number