Most watch faces show you twelve hours so you can find one. Arcminute skips the finding.
Imagine a dial three times wider than your watch. It slides past the screen over the course of the day, and the only part you ever see is the edge nearest the current hour: the numeral, the minute marks around it, and a single hand crossing the screen from a center that never quite fits in view. At 7:15 the hand sits a quarter past the 7. You read it the way you read a speedometer, from where the needle is, not from a diagram of everywhere it could be.
The hand moves continuously, twelve times slower than a minute hand. Watch it long enough and you can see the hour coming.
Two dials: large numerals or a finer classic scale. Nineteen colors for the background and the hand, from a plain black or white to a full saturated palette. In 24-hour mode the numerals renumber themselves so the dial reads 13 through 24 in the afternoon.
No data collected, no permissions, no companion app. It tells the time, sideways.
Arcminute started life on the Pebble smartwatch in 2015. This is the same face, rebuilt for Wear OS.
A dial too large for the screen. You see one hour: the one it is right now.