The core mechanic. As you walk, the app clears circles of fog around you — accumulating across every session. The map stays dark until your feet put you there.
Live heart rate from HealthKit determines how much fog you clear. Easy effort clears a small radius; push into a harder zone and the circle grows significantly. Effort is directly reflected in what you reveal.
Free Walk clears fog as you roam with no set path. Loop generates a circuit that brings you back to your start. Voyager is a one-way walk toward a destination you choose. Three modes, three different ways to explore.
Loop routes are generated for recreational walking, not navigation — randomized each time so the same starting point yields a different circuit. Voyager routes are plotted to feel like a proper walk, not just a straight line to a pin.
Six ranks from Wanderer to Legend, each with a unique ability. Some are passive — a chime as you approach uncharted streets, faint sketches visible through the fog. Others are active, like temporarily doubling your clearing radius.
Each cleared circle earns points based on effort and novelty — pushing harder scores more, and first-time ground scores more than revisited streets. Accumulates across all sessions and drives rank progression.
A heads-up display during active walks shows live zone, distance, and running discovery score. A post-walk summary breaks down fog coverage gained, score earned, and any rank progression from the session.