Instawash

The problem

Customers wanted a car wash at their own address rather than driving to one. Taking those bookings by phone meant someone had to hold the whole schedule in their head — which driver was free, how long the last job was running, whether the next booking was even reachable in time.

What we built

A booking flow where the customer picks a service, an address and a time slot, and only sees slots a driver can actually reach. Behind it, dispatch logic that assigns each job to an available driver and updates both sides live as the job moves from accepted to on-the-way to complete.

The hard part

Not the booking form — the slot availability. Offering a time the business cannot meet is worse than offering fewer times, so the calculation accounts for travel between jobs, service duration by vehicle size, and the driver's actual position rather than a fixed shift pattern.

What it runs on

A Flutter app for both Android and iOS from a single codebase, a Laravel API and database behind it, and a web admin console. Built deliberately data-light, because mobile data in South Africa is expensive and the app has to stay usable on it.