Use Supabase with iOS and SwiftUI

1. Create a Supabase project#

To start, you need a Supabase project.

Create a new Supabase project from the Dashboard of any organization you belong to.

2. Set up your database#

When your Supabase project is up and running, create an instruments table with some sample data. Then set only the privileges each Postgres role needs, add Row Level Security (RLS) for enhanced security for database data by default, and create an RLS policy to make the data in the table publicly readable.

Do these steps within your project's dashboard by copying and running the snippet in your project's SQL Editor.

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-- Create the table
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create table instruments (
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  id bigint primary key generated always as identity,
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  name text not null
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);
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-- Insert sample data into the table
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insert into instruments (name)
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values
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  ('violin'),
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  ('viola'),
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  ('cello');
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-- Grant the privileges the role needs, which is read access
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grant select on public.instruments to anon;
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-- Enable row level security for the table
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alter table instruments enable row level security;
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-- Create a policy to allow the anon role to read from the instruments table
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create policy "public can read instruments"
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on public.instruments
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for select to anon
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using (true);

3. Create an iOS SwiftUI app with Xcode#

Select the Xcode > New Project > iOS > App menu item.

4. Set up AI tooling (optional)#

Supabase provides two ways to give AI tools context about your project: Agent Skills, which give your AI coding agent procedural knowledge, and the MCP server, which connects AI assistants to your Supabase project directly.

Agent Skills#

Agent Skills is a curated set of instructions that give your AI agent procedural knowledge about working with Supabase.

Install them so your AI coding agent can produce more accurate, reliable code using current Supabase patterns, such as authentication, server-side rendering, and database migrations, rather than relying solely on training data.

Installing Agent Skills#

To install, run the following command in the root of your project:

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npx skills add supabase/agent-skills

Supabase MCP server#

The Supabase MCP server connects AI assistants to Supabase, so they can inspect your schema and act on your projects on your behalf. Find out how to add it to your client in the MCP docs.

5. Install the Supabase client library#

Add the supabase-swift package to your app using the Swift Package Manager.

In Xcode, navigate to File > Add Package Dependencies... and enter the repository URL https://github.com/supabase/supabase-swift in the search bar. For detailed instructions, see Apple's tutorial on adding package dependencies.

Make sure to add Supabase product package as a dependency to your application target.

6. Initialize the Supabase client#

Create a new Supabase.swift file and initialize a Supabase client using your project URL and publishable key, which you can get from the helper below, or from the project Connect panel:

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import Supabase
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let supabase = SupabaseClient(
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  supabaseURL: URL(string: "YOUR_SUPABASE_URL")!,
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  supabaseKey: "YOUR_SUPABASE_PUBLISHABLE_KEY"
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)

Get API details#

To interact with data in database tables, you use the client libraries that wrap the auto-generated Data API endpoints, authenticating using the Project URL and key from the project Connect dialog.

7. Create a data model for instruments#

Create a decodable struct to deserialize the data from the database.

Add the following code to a new file named Instrument.swift.

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struct Instrument: Decodable, Identifiable {
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  let id: Int
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  let name: String
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}

8. Query data from the app#

Use a task to fetch the data from the database and display it using a List.

Replace the default ContentView with the following code.

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import SwiftUI
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struct ContentView: View {
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  @State var instruments: [Instrument] = []
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  @State var errorMessage: String?
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  @State var isLoading = true
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  var body: some View {
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    List(instruments) { instrument in
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      Text(instrument.name)
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    }
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    .overlay {
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      if let errorMessage {
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        Text("Error loading instruments: \(errorMessage)")
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      } else if isLoading {
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        ProgressView()
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      }
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    }
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    .task {
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      do {
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        instruments = try await supabase.from("instruments").select().execute().value
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      } catch {
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        errorMessage = error.localizedDescription
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      }
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      isLoading = false
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    }
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  }
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}

9. Start the app#

Run the app on a simulator or a physical device by hitting Cmd + R on Xcode.

10. Setting up deep links (optional)#

If you want to implement authentication features like magic links or OAuth, you need to set up deep links to redirect users back to your app. For instructions on configuring custom URL schemes for your iOS app, see the deep linking guide.

Production requirements#

The quickstart procedure in this guide optimizes for getting you to a working app, not for production.

Before you deploy:

• If your app reads or writes through the Data API, review your Row Level Security policies. Any policy you added here is scoped to this quickstart's sample data, not to real user data.
• Set your Supabase credentials as environment variables on whatever platform you deploy to, rather than committing them to source control.
• Configure a custom domain for your Supabase project once you're ready to go live.

Next steps#

• Learn how to build a complete user management app with authentication in the Swift tutorial
• Explore the supabase-swift library on GitHub
• Insert more data into your database
• Upload and serve static files using Storage