No. There are online functions, but you can use the app fully offline.

The one thing that genuinely needs a connection is the initial offline map download. Once you have downloaded the maps you need you can ride with no signal at all — the map and the routing both run on the device.

Functions that need internet if you choose to use them:

• The DMD HUB — riding groups, location sharing, GPX and profile sync, and Discover
• Satellite and the national topo raster layers
• Hillshading and public GPS traces
• Weather, and the weather map overlays
• Online place and address search — offline search is always there, and a connection adds results when the offline databases find nothing
• The worldwide fire layers, and the country-specific safety modules, which fetch official feeds

Online layers can also be pre-downloaded for an area or along a GPX track, so satellite is available where there is no signal. See Online Layers.