
Multi-platform application in React Native, designed to maximize functional coverage and divide development costs, while ensuring maintainability and security.
Context
Faced with a profound transformation in banking practices and the arrival of a new generation of investors, Milleis has undertaken an ambitious overhaul of its mobile application. Objective: to make the app a key channel in customer relations, in the same way as the advisor.
This redesign aimed to respond to three strategic challenges:
- Attracting younger customers, accustomed to neo-banking and Fintech standards (Revolut, Finary, Wealthsimple...)
- Increase AUM through better product conversion and a more engaging mobile presence
- Increase the operational efficiency of bankers by reducing tasks with low added value (card blocking, RIB editing, limit management, etc.)
Milleis' ambition: to offer a premium digital experience that meets the requirements of its customers, while maintaining the human and personalized DNA of private banking.

Challenges
- Design an application capable of combining daily banking and high-end wealth management
- Quickly improve the efficiency of bankers by digitizing low-value tasks (card blocking, limit management, etc.)
- Deliver a robust, secure, and maintainable cross-platform app.
- Prioritize functionalities and arbitrate costs at the design stage thanks to a design-to-cost approach.
Our approach
The Theodo team of experts, composed of: 1 Head of Delivery, 1 Engineering Manager, 1 Engineering Manager, 1 Tech Lead, 1 Product Owner, 4 mobile developers and 1 Designer, integrated the Milleis teams throughout the duration of the project to create a modular architecture in React Native.
What made the difference:
Just-in-Time
1st user story in production as early as Sprint 0, to secure the speed of execution.
Tech-enabled network of teams
Seamless coordination between bankers, CIOs and compliance.
Right-First-Time
Quality integrated from the design stage with auto, BPMN, CI/CD, pentest tests.

