Milleis
Growing a private bank's app from everyday banking into a full wealth platform, for two very different audiences, in one product.
One app, two worlds.
Milleis's app only did everyday banking. The bank was expanding into investment and wanted the full portfolio on the phone, without alienating its historical clients, and while attracting a newer, more financial profile.
The hard part wasn't features. It was serving two opposite mental models inside a single, coherent product.
How I worked it, end to end.
A continuous loop, not a waterfall, research and testing ran alongside design the whole way through.
I rebuilt how the whole app is navigated.
I mapped every screen and tested several navigation systems with real users. The breakthrough was organising the entire app by interaction depth, ranking information by how much it matters, and how fast it has to be reachable.
Then I ran a workshop with the Comex and the CEO to win buy-in on a bold navigation call.
Two universes in one app.
Rather than averaging the two audiences into one bland middle, I split the app into two visual worlds that share a single navigation and identity, so each client feels at home without fragmenting the product.
Everyday
Warm and beige, the codes of luxury and Milleis's heritage. Familiar and reassuring for historical clients.
Wealth & markets
Darker and focused, with a blue accent I introduced. Built for the new, more financial client.
Two territories, made real.
Same components, same grid, two atmospheres. The shift in colour, contrast and imagery does the work of signalling “which world am I in”, with zero added navigation cost.
One system, the whole app.
I built a solid design system, then worked design-to-cost with engineering: reusing it to ship every feature of the app in just a few months.
App Store ratings climbed within a few months of launch, with user testing strong all the way through.
The redesign earned enough trust to unlock further work, including AI tools for Milleis's private bankers to cut compliance risk.
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