Nerva — web app with full feature parity with the mobile app

Context

A fintech product can’t live on the app stores alone: many users — especially on the business side — work from a desktop, and a web app removes the friction of installation. The challenge was to replicate all the features of the Nerva mobile app in a standalone web app, without duplicating the backend and without letting the two products drift apart. The project is currently in the final stage of development.

What it does

• Replicates the entire mobile app experience — account linking, categorization, reports, budgets — accessible from any browser.
• Shares the same data foundation and the same backend with the mobile app: a user can switch from smartphone to desktop and find everything in sync, with no migrations.
• Adaptive layout: the interface detects the device and reorganizes itself — navigation and information density designed for desktop, a native-app-like experience on mobile.

Technical challenges

Bringing React Native to the web without shortcuts. The web app is not a wrapper around the mobile app but a standalone, lightweight React project: the migration required reimplementing navigation, UI components and state management with the web’s native tools, while keeping the domain logic identical.

Feature parity as a constraint, not a vague goal. Every feature of the mobile app was inventoried (authentication flows, data schema, navigation) and verified against its web counterpart: the 100% parity is measured against that inventory.

One backend, two clients. Data access rules and the data model have to serve both clients without forking: every schema change is designed to stay backward-compatible with the apps already installed.

Stack

React · Vite · Tailwind CSS · Firebase (backend shared with the mobile app) · PWA