In conjunction with paper charts, most sailors these days are navigating via electronic charts displayed on big-screen plotters. The three key manufacturers in the digital chart game are Garmin (Blue Charts), Navionics (Navionics Platinum and Navionics Gold), and Jeppesen Marine (C-Map). The world beneath the water’s surface is an ever-changing one, and to keep out of harm’s way, a navigator must have the most up-to-date charts available. Keeping on track with LNMs, or Local Notice to Mariners, is a good start, but it’s not as comprehensive as downloading a new, updated hard-card chart from Garmin, Jeppesen, or Navionics. Practical Sailor compares their prices and methods for updating their electronic navigation…