As of JourneyMap 3.1.0, you can choose between multiple editions of JourneyMap:

JourneyMap Unlimited Edition has all functionality enabled in both single-player and multi-player Minecraft.

JourneyMap NoRadar Edition is for players who belong to multiplayer servers with rules about mob radar/player radar. All types of radar (mobs, animals, players) are disabled in multiplayer. All features still work in single player.

JourneyMap FairPlay Edition is for players who belong to multiplayer servers with stricter rules. Cave mapping (including Nether and End dimensions) is disabled in multiplayer. All types of radar (mobs, animals, players) are also disabled in multiplayer mode. This edition is for players who want to make use of JourneyMap but avoid anything that could be construed as cheating. All features still work in single player.

Here is a chart comparing the different editions of JourneyMap:

All Editions Unlimited Edition (3.1.0+) NoRadar Edition (4.0.4+) FairPlay Edition (3.1.0+)
Single Player Multiplayer Multiplayer Multiplayer
Web Browser Map
Full-Screen Map
MiniMap (3.3.0+)
Surface Mapping
Cave/Interior Mapping
Nether Mapping
End Mapping
Mob Radar
Animal / Pet Radar
Villager Radar
Other Player Radar (n/a)