How Drop plans routes
Drop plans each driver's route on the dispatcher's iPad, Mac or iPhone, not on a server. An 80-stop day with delivery windows takes about half a second.
What it takes into account
- Real drive times between stops from Apple Maps.
- Delivery windows (“by 10”, “between 1 and 3”), so stops that have one are planned to arrive inside it.
- Service time at each stop: a minute for a parcel, half an hour for a two-person furniture drop.
- Each driver's start and end, shift hours and, on Drop 10 and up, van capacity.
- Your own calls: drag a stop, lock a stop first or last, keep a stop with one driver, then “optimize the rest”.
How it works
Drop builds a first route by inserting each stop where it costs least, stops with delivery windows first. Then it improves the route by reversing and moving short runs of stops, and keeps searching with a seeded random search, keeping the best route that has no late stops. With several drivers it splits the stops between them first, then plans each route. The same request always gives the same route, on the phone and on our server.
During the day, Drop re-plans what's left when you move or add a stop, and keeps the stops already delivered where they are. ETAs are estimates, shown to customers as a window.
The benchmark
We compare Drop against Google's OR-Tools, a widely used industrial route solver, given 10 seconds per route. The test is 40 delivery days on real roads in Austin, Columbus and Phoenix, from 10 to 80 stops, half of them with delivery windows. “vs OR-Tools” is how much longer Drop's day is (driving, service and waiting time). Lower is better; 0% is a tie.