Supabase Auth Screen Template for iOS (Free SwiftUI)

Want a clean Supabase login screen for iOS that is actually secure? The short answer: build the screen, email and magic link, social, and Sign in with Apple, from a design and let Supabase handle accounts and sessions, but do not stop there. The piece that makes auth meaningful is row-level security on your database, so an authenticated user can only touch their own data. Build the screen from a free VP0 design, the free iOS design library for AI builders.

Who this is for

This is for builders using Supabase as their backend who want a polished sign-in screen and need to connect it to real data access rules, not just a login that looks complete but leaves the database open.

Auth screen plus the rule that matters

The Supabase client gives you several sign-in methods: email and password, passwordless magic links, social OAuth providers, and Sign in with Apple, which Apple’s guideline 4.8 requires when you offer other social logins. Supabase manages accounts, issues a session, and refreshes tokens; you build the SwiftUI screen and store the session securely in the keychain. But the part beginners skip is on the database: Supabase exposes your tables through an API, and without row-level security policies, an authenticated user could read other users’ rows. Enabling RLS and writing per-user policies is what turns “logged in” into “can only see my own data.”

Piece	Supabase’s job	Your job
Accounts	Create and manage	Build the screen
Session	Issue and refresh	Store in keychain
Sign in with Apple	Provide the method	Include it (4.8)
Data access	Enforce RLS policies	Write the policies
Errors	Return clear codes	Show friendly states

Build it free with a VP0 design

Pick a login design from VP0, copy its link, and prompt your AI builder:

Rebuild this VP0 login design in SwiftUI with Supabase auth: [paste VP0 link]. Offer email or magic link, a social provider, and Sign in with Apple, store the session in the keychain, and show clear loading and error states. Remind me to enable row-level security and write per-user policies so authentication actually restricts data access.

Sign in with Apple alone reaches a vast base, with Apple reporting more than 2,000,000,000 active devices, so offering it is both required and high-converting. For neighboring auth and backend patterns, see a Firebase iOS auth login with dark mode, fixing a Supabase Google auth popup freeze on iOS, an Apple sign-in template in React Native, and Supabase Edge Functions error handling. To take payments after sign-in, see an Adyen Drop-in checkout UI in SwiftUI.

Secure by default, not by accident

The honest reframe: a beautiful login screen with no row-level security is a false sense of safety. Treat RLS as part of building auth, not a later task, enable it on every table with user data and write policies that scope each user to their own rows, then test by trying to access another user’s data with a normal account. Store tokens in the keychain, never log them, and write friendly errors that do not reveal whether an account exists. Auth done to this standard protects users from the first release.

Common mistakes

The first mistake is shipping auth with no row-level security, leaving data open. The second is offering social logins without Sign in with Apple, failing review. The third is storing the session insecurely instead of the keychain. The fourth is leaking whether an account exists in error messages. The fifth is paying for an auth kit when a free VP0 design plus Supabase does it.

Key takeaways

• Supabase handles accounts and sessions; you build the screen and store it securely.
• Include Sign in with Apple alongside other social logins.
• Enable row-level security and write per-user policies, or data is exposed.
• Keep tokens in the keychain and write non-leaky error states.
• Build the screen free from a VP0 design.

Frequently asked questions

How do I build a Supabase auth screen for iOS? Use the Supabase client for email or magic link, social, and Sign in with Apple, store the session in the keychain, and pair the login with row-level security policies, from a free VP0 design.

What is the safest way to build Supabase auth with Claude Code or Cursor? Start from a free VP0 design, let Supabase handle accounts, include Sign in with Apple, store tokens in the keychain, and enable RLS so auth actually restricts data.

Can VP0 provide a free SwiftUI or React Native template for a login screen? Yes. VP0 is a free iOS design library; pick a login design and your AI tool rebuilds email, magic link, social, and Sign in with Apple at no cost.

Why does Supabase auth need row-level security? Because auth only proves identity; RLS restricts what each user can read and write. Without it, an authenticated user could query others’ data, so enable RLS and write per-user policies.