Eric Pitcock


Mapping the world a better place, one hexagon at a time.

CoverageMap, desktop


Mobile carriers all claim to have the best coverage in the most places. But do they really? CoverageMap shows real coverage and performance based on the results of crowdsourced and RootMetrics’ own testing.

When LTE was introduced, download speed became a huge deal. And carriers started touting their LTE coverage and speed on a national level.

Early CoverageMap versions lacked technology and speed layers and limited how far you could zoom out to roughly the size of Washington State (the state, not the university). So there was no way to verify speed or LTE coverage at a national level. It was time to catch up with the changes in the industry.


  • Introduce a nationwide view of performance.
  • Add new speed and technology layers. Color schemes that work at all zoom levels.
  • Completely redesign the experience for desktop and tablet.


We needed this map to work equally well at nationwide and street levels. Changing the zoom level properties for Google Maps was the easy part. The problem was the same hexagon size that encapsulates a few blocks of a neighborhood was barely a pixel when you zoomed out to a nationwide level. And a hexagon you could distinguish at nationwide level covered entire cities at the street level — hardly a neighborhood view of performance.

The ultimate solution was large hexagons at the nationwide level and small hexagons at the street level, with three transitional layers between them. The large hexagons, which are aggregates of the small hexagons they encapsulated, would fade out to expose the smaller hexagons as the user zooms in.

The green to black scheme for call performance stayed, as it works well for a good to bad range. Technology and speed are different. No technology or speed is necessarily better than another, it’s all relative to how you use your phone. Rather than distinguish good from bad, these layers were designed to emphasize the latest technology and the fastest speeds.

CoverageMap, speed layer

Download speed is likely the most important factor to a typical user. The speed layer used dark blue to call out where the fastest speeds were found.

CoverageMap, call layer

Since signal strength was typically good (green) in most places, so the call performance layer was designed to emphasize the dead zones (red and black).

CoverageMap, technology layer

The technology layer was designed to highlight LTE by giving it the darkest color. This is especially helpful at a nationwide level.

CoverageMap, tablet

Comparison CoverageMap, a spin-off of CoverageMap, was designed specifically for tablet use in Carphone Warehouse stores in the UK.

CoverageMap, sketches

Early sketches and paper prototypes.

CoverageMap, hex size comparison

Testing different hexagon sizes to see how they held up at a nationwide level.

CoverageMap, prototype

Maptool, an internal tool used to test color schemes with real data, was crucial in the process. Shout out to Jon Gleasman.