# Copy the API keys of your RevenueCat apps into .env

The step `revenuecat.api_keys`, for [`revenuecat`](https://doc.saymyframe.com/modules/revenuecat.md).

The app configures RevenueCat with the public API key of a RevenueCat app of the project: the App Store app on iOS, the Play Store app on Android, and the Test Store in a debug build. While the key that a build takes is empty, the app runs without purchases and never calls RevenueCat, and a debug build prints which key to fill in.

These keys are public. Each is compiled into the app, where anyone can read it. A secret API key of RevenueCat, which starts with `sk_`, never goes into the app, and the app refuses one.

:::tip
The examples use the bundle id `com.example.my-app` and the package name `com.example.my_app` of an app that `smf create my_app` generated. Yours start with the organization that you gave `--org`. The screenshots use the project `My App`. The orange frames mark what to click, in the order of their numbers.
:::

**1. Add the apps of the stores.** In the [RevenueCat dashboard](https://app.revenuecat.com/), open the project and click **Apps** in the sidebar (1). Click **New app configuration** (2), or **New app** once the project has an app.

![The page Apps of a RevenueCat project, with Apps in the sidebar marked 1 and the card New app configuration marked 2](https://doc.saymyframe.com/assets/images/apps-new-1201d2d32bcace9a5abd2f5d105a98b3.png)

Choose **App Store** (1) for the iOS app, and then, for the Android app, **Google Play Store** (2).

![The stores of a new app configuration, with App Store marked 1 and Google Play Store marked 2](https://doc.saymyframe.com/assets/images/new-app-stores-19c576b4c75c656f300d350605d6921c.png)

- **App Store**: an app name and the **App Bundle ID** (1) of the iOS app, such as `com.example.my-app`. Xcode shows it under **Bundle Identifier** on the tab **Signing & Capabilities** of the target **Runner**.

![The form New App Store app, with the App Bundle ID com.example.my-app marked 1](https://doc.saymyframe.com/assets/images/app-store-app-b6f94e4477b53f318f3479e1d894a5a4.png)

- **Google Play Store**: an app name and the **Google Play package name** (1) of the Android app, such as `com.example.my_app`, the `applicationId` in `android/app/build.gradle.kts`.

![The form New Play Store configuration, with the Google Play package name com.example.my_app marked 1](https://doc.saymyframe.com/assets/images/play-store-app-5195c0f0420b10e407420b8b9e8abbbc.png)

Click **Save changes** at the bottom of each form. RevenueCat creates the public API key of each app with it. The forms also have a section for the credentials of the store, which the next two steps fill in, and you can add them now or later.

**2. Copy the keys.** Click **API keys** in the sidebar (1). Under **SDK API keys**, click the copy icon of each app: the key of the App Store app (2) starts with `appl_`, and the key of the Play Store app (3) with `goog_`. The Test Store has a row of its own there, with a key that starts with `test_`, and the page **Apps** shows that key too.

![The page API keys, with API keys in the sidebar marked 1 and the copy icons of the keys of the App Store app and of the Play Store app marked 2 and 3](https://doc.saymyframe.com/assets/images/api-keys-7ed8c0a8a292ea1a447634aa6698764a.png)

**3. Put them into .env.** In `.env` at the root of the app:

```bash title=".env"
REVENUECAT_APPLE_KEY=appl_...
REVENUECAT_GOOGLE_KEY=goog_...
REVENUECAT_TEST_KEY=test_...
```

`.env` stays out of git. On another machine, copy `.env.example` to `.env` and fill it in again.

**4. Start the app again.** The `flutter` tool reads `.env` when a command starts, so stop `flutter run` and start it again with the values:

```bash
flutter run --dart-define-from-file=.env
```

Run and Debug of VS Code, and the run configuration of the app in Android Studio, pass the argument for you.

The app chooses the key by the build:

| Build | Key |
| --- | --- |
| A debug build, with `REVENUECAT_TEST_KEY` filled in | The Test Store |
| A debug build without it, and every profile or release build | `REVENUECAT_APPLE_KEY` on iOS, `REVENUECAT_GOOGLE_KEY` on Android |

A release build never takes the key of the Test Store, since RevenueCat stops such a build on purpose. To buy through the sandbox of a store in a debug build, leave `REVENUECAT_TEST_KEY` empty.

**Check.** A debug build no longer prints that a key "has no value in this build", and the paywall shows the plans of the default offering.