> ## Documentation Index > Fetch the complete documentation index at: https://docs.newly.app/llms.txt > Use this file to discover all available pages before exploring further. # Using the cloud simulators > Start your simulator, watch the agent's simulator, use the controls and understand each card state. In Newly v2, at app.newly.app and in Newly for Mac, every Remote chat has two cloud simulators. Remote chats run in the cloud. **Your simulator** is for trying the app yourself. **The agent's simulator** is the one the agent uses to test its work. Both run on devices Newly hosts and stream into the preview pane. For an overview of the pane and the Web view, see [Previewing your app](/preview/overview). The devices are fixed: "iPhone 17 Pro - iOS 26" for iOS and "Pixel 8 - Android" for Android. You can't pick another model or OS version. ## Your simulator Choose **iOS** or **Android** in the **Simulator** pill. A checklist shows progress: "Preparing your app", "Leasing a simulator", "Starting Metro and bundling" and "Installing your app". Press **Cancel** if you change your mind. When the device is ready, its screen appears in the pane. Click and type on it as you would tap and type on a phone. Pressing **Preview** in the chat header does the first two steps for you. In the web app, you may first see a "Prepare your simulator" card. Press **Prepare simulator** to continue. ### What the card says | Card | What it means | What to do | | ------------------------------------- | ------------------------------------------------- | -------------------------------------------------------------------------------- | | "No app to run yet" | There's no build to run yet. | Describe the app you want in the chat, or wait for the agent's first build. | | "Build queued" / "Building your app…" | A native build is waiting or running. | Wait, or press **Cancel build**. | | "Build cancelled" | The build was stopped. | Press **Build again**. | | "Couldn't build your app" | The native build failed. | Press **Build again**. See [Native builds and packages](/preview/native-builds). | | "Couldn't start your simulator" | The device didn't start. | Press **Try again**. | | "Your simulator went idle" | The device was released. | Press **Resume** to start a fresh device with the newest completed build. | | "Build Android for this session" | This chat doesn't have its own Android build yet. | Press **Build Android app**. | ## The agent's simulator The agent's simulator is the device the agent drives while it tests your app. 1. Choose **iOS** or **Android** in the **Agent** pill. 2. Press **Open agent simulator**. 3. Watch the device while the agent works. While the device gets ready, the card shows steps such as "Requesting simulator…", "Building iOS app…" or "Building Android app…", "Leasing simulator…" and "Installing app…". When the agent saves a walkthrough recording of what it tested, **Live** and **Walkthrough** tabs appear above the device. **Live** shows the device now. **Walkthrough** plays the recording. Press **Open replay** to open it in a new tab. If you see "Agent simulator ended", press **Open again** for a fresh device. If you see "Couldn't open the simulator", press **Try again**. ## Controls Hover over the right edge of a running simulator to show its control rail: * **Reload** the app * **Save screenshot to Downloads** * **Home** * **Back** (Android) * **App switcher** (iOS) or **Overview** (Android) * **Rotate** * **Start webcam injection**, which feeds your computer's webcam to the device camera * **Copy from Simulator Clipboard** and **Send to Simulator Clipboard** * **Upload media** (web app only), which adds a JPEG, PNG or MP4 file to the device's photo gallery ## When the code changes * **JavaScript changes** usually appear on your simulator within seconds. Nothing needs reinstalling. * **Native changes**, such as a new native package, need a new build. When the build is ready you see "The agent changed native code. Update to install the new build." Press **Update**. If your simulator failed or went idle while an update was waiting, the button reads **Update and try again** or **Update and resume**. ## Idle simulators Your simulator is released after about 10 minutes without activity. It's also released when the chat parks. Your code and the chat aren't affected. Press **Resume** to start a fresh device with the newest completed build. To learn when a chat parks, see [Parked chats and limits](/build/sleep-and-limits). ## Android builds Android builds wait for a free build worker. The card shows "Waiting for an available Android build worker. Your build will start automatically." You don't need to do anything. If a build waits or runs for too long, it fails and the card tells you how to retry. ## Logs and debug info **On Mac:** in Remote chats, **App Logs** sits at the bottom-right corner of the preview pane. The **Metro** tab (for example **Metro · iOS**) shows the app's JavaScript output. The **Native Build** tab shows build progress and output. **In the web app and on Mac:** when a chat hits a problem, the failure card in the chat has a **Copy debug info** button. Paste the result into your message when you [contact support](/help/getting-help). ## Credits The cloud simulators don't draw down credits. The agent's work in the chat does. See [How credits work](/billing/how-credits-work). ## Related The preview pane, the Preview button and the Web view. What triggers a rebuild and what's preinstalled. Getting your app onto an iPhone. What preview and build messages mean.