Mobile App · Personal Finance
Fin — Personal Finance Management
Your money on your device. No subscription, no ads, no mandatory cloud.
The Android version is implemented and in validation. The Google Play launch is being prepared — the app cannot be downloaded yet.
Executive summary
Fin is a personal finance app built by Vita Munhoz Tecnologia. The Android version is implemented and in validation, ahead of its public launch. It brings together the complete core of a finance manager — transactions, cards with statements assembled automatically, accounts, investments, savings goals, budgeting, a monthly dashboard and reminders — in a mobile experience designed for daily use. Two architectural decisions define the product. The first is being offline-first: everything works without an internet connection, and the cloud is a convenience, not a requirement. The second is treating privacy as a feature rather than a promise: the local database is encrypted, the key lives in the operating system's vault, receipt scanning happens on the device, and the AI assistant only ever receives an aggregated summary — never the raw transaction list. The commercial model planned for launch closes the argument: a one-time purchase on Google Play, with no ads, no subscription and no data selling.
Managing your own money is still too much work
- Spreadsheets demand manual discipline and fall apart in the first busy week.
- Free apps are funded by advertising — which puts them at odds with anyone trying to spend less.
- Many of the alternatives charge a recurring subscription for basic features.
- Apps that centralize financial data on their own servers widen the exposure of sensitive information.
- And without an internet connection, most of them simply stop working.
Who it's for
- People who want to see and control their own spending
- Anyone organizing a budget or working their way out of debt
- Anyone who will not accept a subscription or ads inside a finance app
- Anyone who puts privacy first and does not want financial data on third-party servers
Real screens from the app
Screenshots of the app running — not simulations, not mockups.
Monthly summary
Income, expenses and what is left over this month, with a donut chart by category and the upcoming due dates.
Transactions
The month's entries grouped by period, each with its category and amount.
Cards
Every card with its used and available limit, updated on each purchase.
Card statement
The purchases grouped into the cycle's statement, with the total and the statement payment.
Investments
Portfolio value, returns, allocation by asset class and every position.
AI assistant
A question in plain language and an answer based only on the aggregated summary of your finances.
The figures shown in the screenshots are fictitious.
Key features
What is already implemented in the version under validation.
Full transaction types
Expense, income, transfer between accounts and installment purchase — scheduled or settled.
Receipt scanning (OCR)
The camera reads the receipt and pre-fills the entry. The photo never leaves the device.
Cards and statements
The statement is assembled automatically per cycle, with used and available limit in real time.
Accounts and net worth
Checking, savings, cash and investment accounts, with consolidated net worth.
Budget by category
A monthly spending target that shows what is left — or by how much you went over.
Savings goals
Progress tracked by hand or mirrored from an account balance, with contributions and a target date.
Investments
Fixed income, stocks, funds, REITs, crypto and savings, with returns calculated for you.
Monthly dashboard
Income, expenses, what is left over and a donut chart by category, month by month.
Due-date reminders
Local notifications for scheduled bills and card statements, overdue ones first.
AI assistant
Ask in plain language. It answers from an aggregated summary — and it is the only feature that needs an internet connection.
Backup and import
Export and import a JSON backup; import transactions from a CSV file.
Manual sync
You decide when to sync. Until you do, your entries never leave the device.
Encrypted local database
The data is encrypted on the device, with the key held in the system vault.
Offline-first
The whole app works with no internet — the AI assistant is the only exception. The cloud is a convenience, never a requirement.
Pay once, it's yours
The model planned for launch: a one-time purchase on Google Play. No subscription, no ads and no in-app purchases.
Privacy by architecture
An encrypted database, receipts read on the device and an AI that only ever sees a summary. Not a promise in a policy: it is how the app was built.
Architecture and scalability
- Offline-first: the local database is the source of truth, and no screen depends on the network in order to read.
- An encrypted local database — the app refuses to run on top of an unencrypted one.
- The cloud is a mirror of the local database, used to sync across devices and as a backup. Syncing is triggered by you; it is not automatic.
- Built in Flutter, with a foundation ready for the web as well.
Security
- An encrypted local database, with the key in the system vault (Keystore on Android, Keychain on iOS) and hardware-backed protection where the device supports it.
- Integrity attestation (App Check / Play Integrity): the backend only talks to genuine instances of the app.
- Receipts are read on the device — the image and the text are never sent anywhere.
- The AI assistant receives only an aggregated summary: never the raw transaction list, the entry descriptions or the account names. It is the only feature that sends anything out, and the only one that needs an internet connection.
- The app requires an account to run — your email lives in the identity service. Your entries, on the other hand, only go up if you choose to sync.
- Full account deletion: it erases the identity, the cloud copy and the local data.
Commercial model
At launch: pay once, it's yours
The commercial model planned for launch is a one-time purchase on Google Play — no subscription, no advertising, no in-app purchase and no data selling. The product will not be funded by ads, so there is no incentive to nudge you into spending more. The app is not on the store yet: this is the intended commercial model, not an offer in force.
- A one-time purchase on Google Play — no monthly fee.
- No ads and no third-party trackers inside the app.
- No in-app purchases and no “premium tier”.
- No data selling — and your entries only leave the device if you sync them.
What changes for the people who use it
Concrete benefits, derived from what the product actually does.
A consolidated view of spending, accounts, cards and investments in one place.
The card statement assembles itself — installment purchases included, each in the right month.
Category budgets that warn you before the limit is blown.
Your entries stay encrypted on your device, and only reach the cloud when you choose to sync.
At launch, pay once and it's yours: no subscription and no ads standing between you and your money.
Where the product is, and where it is going
What is marked as implemented has been built and is in validation — it does not mean it is on sale. The rest is a roadmap: intent, not a delivery promise.
Core financial management
Transactions, cards with automatic statements, accounts, investments, savings goals, budgeting, the monthly dashboard and reminders — with the data on the device.
OCR, AI assistant and portability
Receipt scanning through the camera, an assistant that answers questions about your finances from an aggregated summary, JSON backup, CSV import and optional sync across devices.
iOS version
The app is built in Flutter and the iOS foundation already exists, but there is no iPhone version. The track in validation today is Android.
Bank sync (Open Finance)
Automatic connection of accounts and cards via Open Finance. Today the app does not connect to a bank: entries are made by you, read from a receipt or imported from a CSV file.
Multi-platform experience
A desktop and web dashboard, built on the same architectural foundation.
Frequently asked questions about Fin — Personal Finance Management
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