DexNav different crown colors

A crown emblem may appear in the upper right of the DexNav, to indicate the player's progress.

  • Platinum: all of the wild Pokémon in the area are in the player's Pokédex;
  • Gold: the only missing Pokémon are foreign species unlocked by the defeat of Groudon/Kyogre;
  • Silver: the player is missing Pokémon from only one of the other encounter methods (tall grass, fishing and surfing);
  • Bronze: the player is missing Pokémon from two of the other encounter methods;
  • No crown otherwise.

Source: Bulbapedia.