> ## 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.

# Previewing your app

> See your app running on cloud simulators and in the Web view, with nothing to install.

In Newly v2, at app.newly.app and in Newly for Mac, your app runs as a real native development build on a **cloud simulator** that Newly hosts. The simulator's screen streams into the preview pane next to your chat.

There's nothing to install. You don't need a QR code, Expo Go or a phone on the same network.

## The preview pane

The row of pills at the top of the preview pane picks what you're looking at:

| Pill                               | What it shows                                                                          |
| ---------------------------------- | -------------------------------------------------------------------------------------- |
| **Simulator**: iOS, Android or Web | Your own copy of the app. iOS and Android open your simulator. Web opens the Web view. |
| **Agent**: iOS or Android          | The agent's simulator, which the agent uses to test your app while you watch.          |
| **Use this Mac**                   | In Local chats (Mac): switches back to your Mac's own simulator.                       |

The cloud devices are "iPhone 17 Pro - iOS 26" and "Pixel 8 - Android". You can't pick another model or OS version.

## Your simulator and the agent's simulator

Each Remote chat has two cloud simulators.

* **Your simulator** is for trying the app yourself. Tap, scroll and type as you would on a phone. Press **Start my simulator** to open it.
* **The agent's simulator** is the device the agent drives when it tests a change. Press **Open agent simulator** to watch it live. The agent can also save walkthrough recordings of what it tested.

For the controls, card states and what happens when a simulator goes idle, see [Using the cloud simulators](/preview/simulators).

## The Preview button

The **Preview** button in the chat header opens the preview pane and runs whatever your simulator needs next: start it, resume it, install an update, or ask the agent to build the app. It never cancels a build that's already running.

## The Web view

The Web view shows the web version of your app in a browser card. It's available in Remote chats only.

To open it, choose **Web** in the **Simulator** pill.

* The Web view opens at a private address. Only members of the project can open it.
* The first load can take a few minutes while the app server starts. A status line shows what's happening.
* If it fails, you see "App preview failed". In the web app, press **Retry starting preview**. In the Mac app, use the retry button on the card.
* If the chat is parked, the Web view may briefly show "Session is sleeping" while it wakes the chat.

The card's toolbar and its **Preview options** menu give you:

| Option              | What it does                                  |
| ------------------- | --------------------------------------------- |
| **Reload**          | Reloads the page.                             |
| **Frame width**     | Shows the app at Phone, Tablet or Full width. |
| **Open in browser** | Opens the Web view in its own browser tab.    |

If the page stops updating or won't load, open **Preview options**, go to **Ports** and choose **Restart server**.

In the web app, the Web view can ask for camera and microphone access (your browser still asks you first) and can open sign-in popups.

<Warning>
  The Web view isn't an exact copy of your simulator. Features that need a phone, such as some native packages, may not work or may look different on the web. Check them on a cloud simulator.
</Warning>

<Tip>
  For developers: the **Ports** page also lets you change the port the app server uses. Saving restarts the server. Most people never need it.
</Tip>

## In Local chats on your Mac

In Local chats (Mac), the preview pane can use your Mac's own iOS Simulator or Android emulator instead of the cloud simulators. Local chats don't have a Web view. See [Local chats on your Mac](/mac/local-chats).

## Previews and credits

Previews don't draw down credits. That includes the cloud simulators, the Web view and the native builds behind them. The agent's work in the chat does use credits. See [How credits work](/billing/how-credits-work).

## On a real phone

Previews run in the cloud and can't be installed on a phone. To try your iOS app on an iPhone, publish it to TestFlight. An organization owner or admin connects Apple and publishes. Newly v2 doesn't produce Android builds you can install on a phone. See [Testing on a real phone](/preview/test-on-a-phone).

## Related

<CardGroup cols={2}>
  <Card title="Using the cloud simulators" icon="mobile-screen" href="/preview/simulators">
    Controls, card states, idle simulators and logs.
  </Card>

  <Card title="Native builds and packages" icon="hammer" href="/preview/native-builds">
    What triggers a rebuild and how long it takes.
  </Card>

  <Card title="Testing on a real phone" icon="mobile" href="/preview/test-on-a-phone">
    iPhone through TestFlight, and what isn't available.
  </Card>

  <Card title="Parked chats and limits" icon="moon" href="/build/sleep-and-limits">
    What happens when a chat is idle.
  </Card>
</CardGroup>