Full Stack React Native Course - Build Welth (Full Stack App for IOS and 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.

Features

• Accounts — multiple accounts (cash, bank, credit card, savings) with a default account and running balances
• Transactions — income/expense tracking with categories, search, filters, and daily income vs. expense charts
• AI receipt scanning — snap or pick a photo of a receipt and let Gemini extract the amount, category, and description
• AI voice entry — describe a transaction out loud ("I spent 400 on groceries yesterday") and have it transcribed and parsed automatically
• Monthly budget — set a budget and track spend against it on the dashboard
• CSV export — export recent transactions to CSV and share them from the Transactions screen
• AI assistant — ask questions about your spending
• Onboarding — first-run currency and starting balance setup

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
• 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. 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. Run the Supabase queries below to set up 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=        # "Welth <alerts@yourdomain.com>" once you verify a domain in Resend;
                              # until then, use "Welth <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 "Welth" 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 Welth logo, used in the email header;
                              # omit this secret entirely to fall back to a text "Welth" 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.