Where it came from
It started as a sheet of paper on the desk.
Exercise snacking is the idea — not ours — that a few minutes of movement every hour does you more good than one block of it a day, and is far easier to keep up. It suits anyone whose day is spent tied to a desk, which is where we started: ten press-ups between meetings beats a gym you never get to. The obvious way to keep count is a grid — hours across the top, a tick in each box — and that's what was on the desk.
Paper has three problems. You can't see it from the kitchen. It doesn't nag you at three o'clock when the last box was at eleven. And just when you need to fill it in, the cat is sat on it.
So Dash is that grid, kept on the devices you already carry. A box is one hour. A tap fills it. The tally, the run and the week beside it take care of themselves. It's called Dash in the salt sense. Every box is a dash of something — exercise, water, a walk — a little, often, rather than a lot, once.