# Get set up

Install the SDK and send your first signal. Two lines, and you're watching live data land in your dashboard.

Source: https://cross-deck.com/university/get-set-up/
Verified Crossdeck University lesson — prose plus real, runnable code.

## One SDK, then everything else is data

Everything in Crossdeck — identity, entitlements, revenue, errors — rides on one SDK sending verified signals from your app. This first step is the foundation: get the SDK in, initialise it once, and confirm a live signal. Every other lesson builds on this one setup.

## Add the SDK for your platform

On the web it's one package; on iOS it's a Swift Package.

```web
npm install @cross-deck/web
```

```swift
// In Xcode: File → Add Package Dependencies…
// https://github.com/cross-deck/crossdeck-swift
```

## Initialise once, with your publishable key

Call init once when your app boots. It takes three things: the app ID for this platform, the publishable key from your project's API keys page (safe to ship in client code), and the environment so sandbox traffic never pollutes production. That's the only configuration there is.

```web
import { Crossdeck } from "@cross-deck/web";

Crossdeck.init({
  appId: "app_web_acme01",
  publicKey: "cd_pub_live_xxx",
  environment: "production",
});
```

```swift
import Crossdeck

let cd = try? Crossdeck.start(options: CrossdeckOptions(
    appId: "app_ios_acme01",
    publicKey: "cd_pub_live_xxx",
    environment: .production
))
```

## Your first verified signal, live

Run your app and open the dashboard. Within seconds the session appears live on the map — that's your first verified signal, and the proof the SDK is wired correctly.

1 active now
 A live session just landed on the map — the SDK is sending verified signals. You're set up.