> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mobilerun.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Playground

> Test and optimize your agent configurations interactively before deploying to production.

The Playground is your interactive environment for testing agent prompts and configurations on real devices. Use it to iterate quickly on your automation logic without writing code.

## Overview

The Playground allows you to:

* Test agent prompts in real-time
* Observe how your agent interacts with the device
* Iterate on prompt wording and task instructions
* Validate automation flows before production deployment

## Selecting a Device

Before running a task, select a device from your account — a Personal Phone, Cloud Phone, or Physical Phone.

<Tip>
  Not sure which device type to use? See the [Device Types](/device-types) documentation to understand the differences between Personal Phones, Cloud Phones, and Physical Phones.
</Tip>

## Running a Task

1. **Select your device** from the device dropdown
2. **Enter your prompt** describing what the agent should do
3. **Click Run** to start the task
4. **Observe** the agent's actions in the device stream

The agent will interpret your prompt and execute the corresponding actions on the device. You can watch the device screen update in real-time as the agent performs each step.

## Prompt Optimization

The Playground is designed for rapid prompt iteration. Use it to:

| Technique               | Description                                                    |
| ----------------------- | -------------------------------------------------------------- |
| **Refine instructions** | Adjust your prompt wording to get more accurate agent behavior |
| **Test edge cases**     | Verify how your agent handles unexpected UI states             |
| **Compare approaches**  | Try different prompt styles to find what works best            |
| **Debug failures**      | Identify why a task failed and adjust your instructions        |

### Writing Effective Prompts

Good prompts are specific and action-oriented. Here are some guidelines:

**Be explicit about the goal**

```
Open the Settings app, navigate to Display, and set brightness to 50%
```

**Include context when needed**

```
In the Gmail app, compose a new email to test@example.com with subject "Test" and body "Hello"
```

**Break down complex tasks**

```
1. Open Chrome
2. Navigate to github.com
3. Click the Sign In button
4. Enter username "testuser"
```

## Session Management

Each Playground session maintains state until you end it or switch devices:

* App installations persist within the session
* Login states are maintained
* Files created during the session remain accessible