💰 FinTrack — Full Stack Budgeting App (iOS & Android)

A full-stack budgeting app for iOS and Android built with Expo and Supabase — track accounts and transactions, set a monthly budget, and log expenses by typing, scanning a receipt, or just speaking to it.

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📱 APK Download

Click the button below to download and install the app on your Android device:

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✨ Features

• 🏦 Accounts — Manage multiple accounts (cash, bank, credit card, savings) at once. Mark one as your default so new transactions land in the right place automatically, and see a running balance update in real time as you spend or earn.

• 🧾 Transactions — Log income and expenses with categories, then search and filter your history to find exactly what you're looking for. Daily income vs. expense charts give you an at-a-glance view of your cash flow trends over time.

• 📸 AI Receipt Scanning — Snap a photo of a receipt (or pick one from your gallery), and Gemini automatically extracts the amount, category, and description — no manual typing needed.

• 🎙️ AI Voice Entry — Just say it out loud: "I spent 400 on groceries yesterday." FinTrack transcribes your voice, parses the details with AI, and logs the transaction for you.

• 📊 Monthly Budget — Set a spending limit for the month and track your progress against it right from the dashboard, so you always know how much room you have left.

• 📤 CSV Export — Export your recent transactions to CSV and share them straight from the Transactions screen — handy for backups, taxes, or spreadsheets.

• 🤖 AI Assistant — Ask natural-language questions about your spending — "How much did I spend on food this month?" or "Am I over budget anywhere?" — and get instant answers based on your real transaction data.

• 🚀 Onboarding — A smooth first-run flow to set your currency and starting balance, so the app is ready to use in seconds.

• 📬 Smart Email Alerts (backend) — Get emailed automatically when you cross 80% or 100% of your monthly budget, plus a weekly digest of personalized AI-generated spending tips based on your last 7 days of activity.

🛠️ Tech Stack

• ⚛️ Expo (SDK 54) + Expo Router
• 🔐 Clerk for authentication
• 🗄️ Supabase (Postgres + Row Level Security) as the backend, authenticated via Clerk's native third-party auth integration (no Supabase JWT template needed)
• 🧠 Google Gemini for receipt/voice extraction and AI features
• 🎨 NativeWind (Tailwind for React Native)
• 🐻 Zustand
• 🔄 TanStack Query
• ✅ React Hook Form + ZOD

🚀 Get Started

1. Install dependencies

   npm install

2. Add a .env file in the project root with:

   EXPO_PUBLIC_CLERK_PUBLISHABLE_KEY=
   EXPO_PUBLIC_SUPABASE_URL=
   EXPO_PUBLIC_SUPABASE_KEY=
   EXPO_PUBLIC_GEMINI_API_KEY=
   

3. Connect Clerk to Supabase — In your Supabase project, add Clerk as a Third-Party Auth provider (Authentication → Sign In / Providers → Clerk) so auth.jwt()->>'sub' resolves to the Clerk user id — this app does not use the legacy Supabase JWT template approach.

4. Set up the database — Run the Supabase queries below to create the schema.

5. Start the app

   npx expo start -c

   In the output, you'll find options to open the app in a:

   • 🛠️ development build
   • 🤖 Android emulator
   • 🍎 iOS simulator
   • 📦 Expo Go, a limited sandbox for trying out app development with Expo

🗄️ Supabase Queries

👤 Users Table

create table users (
  clerk_id text primary key,
  email text not null,
  name text,
  image_url text,
  currency text, -- null until the user completes onboarding
  created_at timestamp with time zone default now()
);

🔒 Users RLS Policies

alter table users enable row level security;

create policy "Users can insert own row"
on users for insert
with check (clerk_id = auth.jwt()->>'sub');

create policy "Users can read own row"
on users for select
using (clerk_id = auth.jwt()->>'sub');

create policy "Users can update own row"
on users for update
using (clerk_id = auth.jwt()->>'sub');

🏦 Accounts Table

create table accounts (
  id uuid default gen_random_uuid() primary key,
  user_id text not null references users(clerk_id) on delete cascade,
  name text not null,
  type text not null, -- 'CASH' | 'BANK' | 'CREDIT_CARD' | 'SAVINGS'
  balance numeric not null default 0,
  is_default boolean not null default false,
  created_at timestamp with time zone default now()
);

🔒 Accounts RLS Policies

alter table accounts enable row level security;

create policy "Users can manage own accounts"
on accounts for all
using (user_id = auth.jwt()->>'sub')
with check (user_id = auth.jwt()->>'sub');

🧾 Transactions Table

create table transactions (
  id uuid default gen_random_uuid() primary key,
  user_id text not null references users(clerk_id) on delete cascade,
  account_id uuid not null references accounts(id) on delete cascade,
  type text not null, -- 'INCOME' | 'EXPENSE'
  amount numeric not null,
  category text not null,
  description text,
  date timestamp with time zone not null default now(),
  status text not null default 'COMPLETED',
  input_method text not null default 'MANUAL', -- 'MANUAL' | 'RECEIPT_SCAN' | 'VOICE'
  voice_transcript text,
  is_flagged boolean not null default false,
  flag_reason text,
  created_at timestamp with time zone default now(),
  updated_at timestamp with time zone default now()
);

🔒 Transactions RLS Policies

alter table transactions enable row level security;

create policy "Users can manage own transactions"
on transactions for all
using (user_id = auth.jwt()->>'sub')
with check (user_id = auth.jwt()->>'sub');

📊 Budgets Table

-- One budget per user (simple monthly budget, no per-category breakdown)
create table budgets (
  id uuid default gen_random_uuid() primary key,
  user_id text not null unique references users(clerk_id) on delete cascade,
  amount numeric not null,
  last_alert_sent timestamp with time zone,
  last_alert_threshold numeric, -- last budget-usage % (80 or 100) emailed for, resets each calendar month
  created_at timestamp with time zone default now(),
  updated_at timestamp with time zone default now()
);

🔒 Budgets RLS Policies

alter table budgets enable row level security;

create policy "Users can manage own budget"
on budgets for all
using (user_id = auth.jwt()->>'sub')
with check (user_id = auth.jwt()->>'sub');

📬 Budget Alerts & Weekly Tips

Two Supabase Edge Functions in supabase/functions/ run on a schedule and email the user via Resend:

• 🚨 check-budget-alerts — Runs daily, emails a user the first time they cross 80% and again the first time they cross 100% of their monthly budget (tracked via last_alert_sent/last_alert_threshold, resets each calendar month).
• 💡 weekly-tips — Runs every Monday, asks Gemini for a few short, personalized tips based on each user's last 7 days of transactions and emails them.

Neither is called from the app — they're standalone, timer-driven backend jobs that live entirely on Supabase.

⚙️ Setup

1. Link the project (one-time; skip if using the dashboard only)

   npx supabase login
   npx supabase init
   npx supabase link --project-ref <your-project-ref>

2. Apply the DB schema — Supabase dashboard → SQL Editor → run scripts/schema.sql.

3. Deploy the two edge functions — either:

   npx supabase functions deploy check-budget-alerts
   npx supabase functions deploy weekly-tips

   or from the dashboard: Edge Functions → Deploy a new function, paste in the contents of the corresponding index.ts (and the files under _shared/), and give it the same name as the folder — no CLI required.

4. Set secrets (project-wide, covers both functions) — either npx supabase secrets set KEY=value per line below, or dashboard → Edge Functions → Secrets:

   RESEND_API_KEY=
   RESEND_FROM_EMAIL=        # "FinTrack <alerts@yourdomain.com>" once you verify a domain in Resend;
                              # until then, use "FinTrack <onboarding@resend.dev>" — the address must
                              # stay onboarding@resend.dev and only delivers to the email you signed
                              # up with, but the display name (the "FinTrack" part) is yours to set
   GEMINI_API_KEY=           # same Gemini key as EXPO_PUBLIC_GEMINI_API_KEY, without the EXPO_PUBLIC_ prefix
   EMAIL_LOGO_URL=           # any public URL to the FinTrack logo, used in the email header;
                              # omit this secret entirely to fall back to a text "FinTrack" wordmark
   

   SUPABASE_URL and SUPABASE_SERVICE_ROLE_KEY are provided automatically in the edge function runtime — Supabase reserves the SUPABASE_ prefix, so you can't (and don't need to) set these yourself.

5. Schedule them — SQL Editor → run scripts/cron_jobs.sql, after filling in your real project URL and service-role key in the two vault.create_secret(...) calls at the top.

✅ Once done: check-budget-alerts runs daily at 9am UTC, weekly-tips runs Mondays at 9am UTC.

🧪 Testing Without Waiting for the Schedule

Easiest way: dashboard → Edge Functions → select the function → use the built-in test/invoke panel to trigger it on demand and see the response and logs right there.

CLI alternative: curl the deployed URL directly (this CLI version has no functions invoke subcommand):

curl -i --location --request POST 'https://<project-ref>.supabase.co/functions/v1/check-budget-alerts' \
  --header 'Authorization: Bearer <anon-or-service-role-key>'

A response of {"sent": 0} just means no user currently qualifies — for check-budget-alerts you need a test user whose spend is ≥80% of their budget, for weekly-tips a test user with a transaction in the last 7 days. last_alert_sent/last_alert_threshold block repeat sends within the same month, so reset them on your test budget row between runs if you want to re-trigger the same threshold.