LumynFi
A personal finance organizer for people juggling more than one currency.
Open LumynFi- Built by
- Surface IT
- Year
- 2026
- Duration
- In active development
- Our role
- Product · Design · Engineering · Operations
The project
LumynFi keeps accounts, transactions, bills and reminders in one place. It is an organizer for money you already have: it records and arranges, and it never tells you what to do with it.
The challenge
People who earn, spend or send money in more than one currency end up reconciling by hand across apps and spreadsheets. Existing tools either assume a single currency or cross the line into financial advice.
Our solution
A single organizer across phone and web that handles 67 currencies, keeps the same numbers on every device, and stays deliberately non-advisory. It shows you your money clearly and leaves the decisions to you.
Services
Technologies
The stack behind it
Mobile
Flutter, one codebase for iOS and Android
Web
Next.js
Platform
Runs in production, operated by us
How it came together
Business problem
Multi-currency households and freelancers reconcile their money by hand because their tools assume one currency.
Research
We used the earliest builds ourselves, in the currencies we actually get paid in, and fixed what broke.
Strategy
Be an organizer, not an adviser. That constraint decided most of the product.
Design process
A calm, legible interface that shows balances without nagging or scoring the user.
Development
One Flutter codebase for both mobile platforms alongside a Next.js web app, so the numbers cannot drift apart.
Testing
Verified on physical iOS and Android hardware and on the web before every release, because the platforms must agree.
Deployment
Released through the app stores and the web, and operated by the person who built it.
Results
A live product anyone can sign up for and evaluate today.
Lessons learned
Running your own product in production teaches you what a client's product will need at 2am.
- The same figures on phone and web, always reconciled
- Readable in both light and dark
- Localized number and currency formatting
- Statements exportable as PDF
Built so the mobile apps and the web app read from one source of truth, which is why a balance never disagrees with itself between devices.
LumynFi is live and open to the public on iOS, Android and the web.
67
Currencies supported
3
Platforms
Live
In production today
LumynFi, as it runs today
Captured from lumynfi.com. Open it and you will see the same screens.
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