Finance App Boilerplate for iOS: a secure auth + biometrics base for budgeting and trackers
Skip the part of a budgeting or finance-tracker app that has to be airtight from day one: who the user is, how they sign in, and how their data is protected. The Swift Kit gives you Supabase email + Sign in with Apple auth, a server-side proxy layer so secrets never ship in the binary, and a clean SwiftUI base you can extend with Face ID gating — so you can spend your time on categories, charts, and cash flow instead of the login screen.
A finance app boilerplate for iOS, The Swift Kit ($99 one-time) gives budgeting and tracker apps a production-ready security base: Supabase email auth plus Sign in with Apple, Postgres with per-user row isolation, and server-side Edge Functions so API keys never ship inside the app. Because the auth layer is real (not a mock), you can wrap sensitive screens behind Face ID / Touch ID and ship a finance tracker where money data is gated from the first launch. It includes unlimited commercial projects, lifetime updates, and a 14-day refund.
Why a finance app starts with auth, not screens
Most app boilerplates treat login as a checkbox. For a budgeting or finance-tracker app it is the foundation everything else sits on. The moment a user connects a balance, logs a transaction, or sets a savings goal, you are storing data they consider private — and a flaky or mocked auth layer is not something you can patch in later. The Swift Kit ships real Supabase auth: email/password and Sign in with Apple, backed by Postgres where each user's rows are isolated. That means your first finance screen can already assume a verified, scoped user instead of you stubbing one out and reworking it before launch.
The biometric gate you build on top
A finance tracker needs more than a login — it needs a lock. The expected pattern is a fast re-auth: the user signs in once, then Face ID or Touch ID gates the app each time it comes to foreground, so a glance at a budget doesn't require typing a password but a stolen unlocked phone still can't see balances. The Swift Kit gives you the authenticated session and the SwiftUI surface to build this on, rather than a half-finished login you have to replace first.
- Supabase session persists, so biometric unlock re-gates the UI without re-typing credentials
- LocalAuthentication (Face ID / Touch ID) wraps sensitive views you designate as money screens
- Feature flags let you toggle the auth and Apple Sign-In modules on or off per build
- Falls back cleanly to passcode/manual sign-in when biometrics are unavailable
Keeping financial data off the device and out of the binary
The fastest way to leak a finance app is to embed a third-party key (a banking aggregator, an AI categorizer, an analytics token) directly in the app where anyone can extract it. The Swift Kit routes those calls through Supabase Edge Functions: the secret lives server-side, the app calls your function, and the function calls the vendor. The same Edge Functions enforce per-user rate limiting, so one account can't hammer an expensive endpoint and run up your bill — useful when you add AI-powered receipt scanning or transaction categorization to a tracker.
- Edge Functions proxy OpenAI, Claude, or any vendor key server-side — never shipped in the app
- Per-user serverless rate limiting caps abuse on costly endpoints
- Apple Foundation Models run free and on-device for categorization that never leaves the phone
- Supabase storage handles receipt images and exports with the same auth scope
Where this boilerplate stops (and what you still build)
Be clear-eyed: The Swift Kit is a secure auth and app foundation, not a finished finance product. It does not include bank-account aggregation (Plaid/Finicity), double-entry accounting logic, budgeting math, or charting tuned for cash flow — those are your app's actual value and you build them. If your finance app's hard part is regulatory connectivity to bank feeds, the boilerplate saves you the auth/payments/secrets plumbing but not the integration itself. What it removes is the weeks of undifferentiated work — login, sessions, the secrets proxy, paywall via RevenueCat — so the budgeting logic is the first real thing you write.
The Swift Kit vs. building the finance app base from scratch
| Feature | The Swift Kit | Build from scratch |
|---|---|---|
| Email + Sign in with Apple auth | Wired to Supabase, ready | Days to weeks to build and test |
| Per-user data isolation | Supabase Postgres, scoped | You design and secure it |
| Secrets kept out of the binary | Edge Function proxy included | Easy to get wrong, common leak |
| Biometric gate base | Real session to build Face ID on | Build on top of your own auth first |
| Paywall for premium tiers | RevenueCat integrated | StoreKit + receipt logic by hand |
| Bank aggregation (Plaid etc.) | Not included — you add it | Not included — you add it |
| Cost | $99 one-time | Weeks of your time |
Frequently Asked Questions
Does the finance app boilerplate include Face ID / biometric login out of the box?
Where are financial API keys stored — are they safe?
Can I use this for a budgeting app that connects to bank accounts?
How does it isolate one user's financial data from another's?
Can I charge a subscription for premium budgeting features?
Is $99 a subscription, and can I ship more than one finance app with it?
Keep exploring
Ship the finance app, not the login screen
Start your budgeting or tracker app on a real secure base — Supabase auth, Sign in with Apple, a session you can gate behind Face ID, and secrets kept out of the binary. $99 one-time, lifetime updates, 14-day refund.
Get The Swift Kit — $99One-time purchase · Lifetime updates · 14-day refund