Zenzop: delivery apps built for the last mile

Problem

Zenzop is an on-demand delivery app: food, groceries, medicines, and daily essentials brought to your door. Delivery lives or dies on two things the customer feels directly: do I know where my order is, and is the ETA honest. My job was to build the apps that carry both, from scratch, for iOS and Android.

Decisions

Two apps, one job. I built both sides end to end in React Native: the Shop app the customer orders from, and the Rider app the delivery partner runs. Each shipped to iOS and Android, so a small team could move on all four surfaces at once. Google Maps handles real-time geolocation and route optimization, the spine both apps share.

Live tracking that survives a locked phone. A rider’s phone spends the whole trip in a pocket. I built background live tracking so the rider’s position keeps flowing even when the app is not in the foreground, and on iOS I went native with Swift to drive Live Activities: order status and rider progress on the Dynamic Island and lock screen, so the customer sees where their food is without opening anything. That is the difference between an app people check and an app people trust.

An ETA engine, not an ETA guess. A delivery ETA is a promise. I built an engine that computes it from distance matrices, live traffic, the rider’s live position, and historical averages for the route, rather than a naive straight-line estimate. It improved ETA accuracy by 28%, the kind of number a customer feels on every single order.

Fast to load, fast to fix. I refactored the apps for 30% faster load times and wired up CodePush, so over-the-air updates ship straight to users without a full store release. Fixes and tweaks land the same day, not the next review cycle.

Docs so the API is not a bottleneck. I wrote comprehensive Swagger API documentation so the client and backend teams could build, test, and integrate against a single source of truth instead of tribal knowledge.

Outcome

Both apps shipped on iOS and Android: a customer app and a rider app built from nothing, with live tracking that holds up in a pocket, iOS Live Activities on the Dynamic Island, and an ETA engine 28% more accurate than the baseline. The last mile is the part of delivery a customer actually experiences, and these apps were built to make it feel handled.