Define Multiple Apps

Use launch cells to split one Quarto document into several isolated Gradio apps.

Each launch cell closes one source segment and creates one embedded app. A launch cell contains the literal .launch( pattern. Two .launch() calls in one cell still create one embedded app. The filter clears the collected Python source after that cell, so the next app must define or import everything it uses.

Create two apps

two-apps.qmd

---
title: Two apps
filters:
  - gradio
execute:
  enabled: false
---

## Greeting

::: {#08adc50d .cell}
``` {.python .cell-code}
import gradio as gr

def greet(name):
    return f"Hello {name}!"

gr.Interface(greet, "textbox", "textbox").launch()
```
:::


## Uppercase

::: {#990db6db .cell}
``` {.python .cell-code}
import gradio as gr

def emphasize(text):
    return text.upper()

gr.Interface(emphasize, "textbox", "textbox").launch()
```
:::

Render the document and wait for both apps to start. Enter a name in the first app and text in the second. Each app responds independently because the default gives it a dedicated worker.

Live result

The live page uses shared-worker: true so both examples can reuse one Pyodide interpreter and installed package environment. Each app still receives a separate app ID, working directory, and __main__ module.

import gradio as gr

def greet(name):
    return f"Hello {name}!"

gr.Interface(greet, "textbox", "textbox").launch()

import gradio as gr def greet(name): return f"Hello {name}!" gr.Interface(greet, "textbox", "textbox").launch()

import gradio as gr

def emphasize(text):
    return text.upper()

gr.Interface(emphasize, "textbox", "textbox").launch()

import gradio as gr def emphasize(text): return text.upper() gr.Interface(emphasize, "textbox", "textbox").launch()

Split one app across cells

Python source can span several cells before the launch cell:

split-app.qmd

::: {#b937245e .cell}
``` {.python .cell-code}
import gradio as gr

def greet(name):
    return f"Hello {name}!"
```
:::


::: {#e0d7ca6a .cell}
``` {.python .cell-code}
demo = gr.Interface(greet, "textbox", "textbox")
demo.launch()
```
:::

The first cell does not create an app. Its source becomes part of the app closed by the second cell.

Configure apps separately

Put #| gr-* options on each launch cell:

#| gr-theme: light
#| gr-playground: true
#| gr-layout: vertical
demo.launch()

These options apply to that app and override matching values under document-wide gradio.attributes. App requirements and runtime URLs remain document-wide.

The default worker isolation repeats Python startup for each app. Read Runtime and Trust before using shared-worker: true to share one Python environment.