A type scale for cracked screens
Half the phones on a trail crew have a crack across the screen. A small type scale that stays legible through a spiderweb, in full sun, with gloves on.
We counted: eleven of the twenty phones on our last field test had a cracked screen. The cracks are not going to be fixed, so the type has to work through them.
Fewer sizes, heavier weights
The map uses four sizes and two weights. The smallest label is 13 pixels in semibold; anything smaller vanished behind the cracks in our tests.
Room around every label
Each label gets a halo the color of the map behind it, so a line of the trail never runs through a word. It costs a little drawing time and saves a lot of squinting.