Eren Sarıbay

Fibi

Say one sentence; the expense and the item are both recorded.

A mobile app that turns a single sentence like “bought headphones for 3700 lira” into both an expense and an inventory record.

Role
Product, mobile app, server
Year
2026
Status
Test build
Stack
React Native · Expo · TypeScript · SQLite · LLM
Links
WebsiteAppSource

Architecture

Architecture

Live demo · Prototype illustration, not a real screenshot
  1. 01

    Interface

    React Native + Expo. Voice, text or a product link all land on the same preview-and-confirm card.

  2. 02

    On-device parser

    Rule based, works without any key. Clear sentences are understood without leaving the phone.

  3. 03

    LLM fallback chain

    Only for unclear sentences. Amount and date are always verified in code.

  4. 04

    Local data

    SQLite, a daily local backup, JSON export with photos and CSV.

Screens

01 / 05

Home

This month’s total, upcoming installments and subscriptions at a glance.

Real screenshots, matched to language and theme

How it works

One input, two records

Say “bought headphones for 3700 lira” and Fibi adds a ₺3,700 expense and puts the headphones in the inventory under Tech › Audio. “640 lira at the grocery store” is just an expense. Installments land on their due dates, subscriptions come in by themselves every month, and next month’s total is visible up front.

Rules first, then the LLM

Clear sentences are understood by a rule-based parser on the phone, with no internet or key needed. Only sentences it is unsure about go to an LLM, and the amount and date that come back are still checked in code. In daily use the rules turned out to be more consistent, which is why it is built in this order.

Pauses in the middle of a sentence

The phone’s speech recognition could stop at a short pause and cut the amount in half. So I added “smart continue”: recording does not end at the first silence, and alternative transcripts and amounts are offered when needed. Everything that comes from voice is confirmed on the review card before it is saved.

Data stays on the device

No account needed: everything lives in SQLite on the phone, with a daily backup and JSON or CSV export. Expense suggestions from bank SMS are optional and the SMS text never leaves the phone. You can add your own AI key, which is kept only in the phone’s secure storage.