The challenge

58.4% of Brazilian families say money affects their family life. Bruna, our persona, works long hours, has little free time and tracks her money between her bank app and a notebook. She needed to log expenses in seconds, remember bills before they are due and split costs with the people she lives with.

The differentiator: household members

In our research, 16 out of 18 people split bills or receive help with expenses. Still, none of the apps we benchmarked treated household finances as something shared. We created household members: you invite the people you live with by email, electricity, internet and grocery bills are split automatically, and everyone sees how much they owe and who has already paid, with no awkward reminders. Joint income shows the household budget, not just the individual one.

The solution

An Android app with 4 tabs and a central button to log expenses in 3 taps, with its own number pad. Home brings together the balance, this week's bills with a direct pay action, and recent expenses. Main actions sit in the lower third of the screen, following the thumb rule for one-handed use on public transport.

Process and deliverables

Desk research, interviews, a survey, CSD matrix, personas, journey map, benchmark, card sorting, flows and UX writing in FigJam. In Figma, 24 screens in wireframe and high fidelity, a clickable prototype with 4 flows and a design system with variables, semantic tokens, 13 text styles and 21 components with states and micro-interactions. Accessibility follows WCAG 2.2 AA: minimum 4.5:1 contrast, 48 dp touch targets, visible focus and information that never relies on color alone.