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Run Power App (preview)

The Run Power App action launches an app directly from a desktop flow and establishes a communication channel between the two. By using this integration, desktop flows can natively call Power App experiences, pass inputs, and receive outputs. This approach enables rich native integration for attended automation scenarios instead of relying on UI-based automation.

With this capability, you can:

  • Invoke an app directly from a desktop flow
  • Call an app directly from a desktop flow.
  • Pass inputs from the desktop flow into the app.
  • Capture outputs from the app back into the flow.
  • Trigger subflows from app events.

This enables scenarios, such as:

  • Multi-step, dynamic guided forms for attended automation
  • Modern app-based experiences replacing legacy custom forms
  • Event-driven attended automation, where user actions dictate flow execution
  • Modern cloud applications bridging legacy desktop automation

Requirements and availability

  • Minimum Power Automate for desktop version: 2.68 or later.
  • Cloud availability: Available only in public clouds.

Note

This feature is in preview and might change before general availability.

Prerequisites

Before you start, make sure you have:

  • Power Automate for desktop (PAD) version 2.68 or later installed
  • Access to Power Apps in the same environment
  • Desktop subflows you can call from the app
  • Microsoft Edge WebView2 Runtime installed (required to display the Power App during runtime)

Important

  • Create local subflows and define input/output variables in the subflow scope if needed.
  • Subflow names must start with a letter, contain only Latin characters, and have no spaces. Subflows that don't follow these naming rules aren't exposed in Power Apps Studio and aren't available for invocation.

Step 1: Create callable subflows in your desktop flow

  1. Open your desktop flow in the PAD designer.
  2. Create one or more local subflows.
  3. (Optional) For each subflow, define:
    • Input variables: values the app passes into the subflow
    • Output variables: values the subflow returns to the app

Note

You can also create subflows that don't require inputs or outputs. The app can invoke these subflows to execute logic without passing or returning data. Keep each subflow focused on a single operation (for example, look up data, validate input, write to a system).

Step 2: Establish the authoring connection to Power Apps Studio

To expose your subflows in Power Apps Studio (so they appear as functions you can call), open the app through the PAD authoring bridge.

  1. Add the Run Power App (Preview) action to your desktop flow.
  2. In the action properties, either:
    • Select an existing app, or
    • Create a new app

Note

If you create a new app:

  • The Power Automate for desktop bridge page opens automatically in your default browser.
  • Save and publish the app in Power Apps designer.
  • Return to the action and select Refresh.
  • Select your app from the dropdown.

  1. Select Open app.

    Your default browser opens a Power Automate for desktop page that guides you through connecting to Power Apps Studio.

  2. On the browser page, select Open Designer.

    A new browser tab opens with Power Apps Studio, with the selected app already open.

  3. Keep the Power Automate for desktop browser page open until it shows that it's connected.

    If you close the page before the app finishes loading, you prevent establishing a connection between the desktop flow and the Power app.

Step 3: Call desktop subflows from the Power App

After you establish the designer connection, Power Apps Studio shows a host object named PowerAutomateDesktop. This object exposes your desktop subflows as callable functions.

Invocation pattern (general)

To call a desktop subflow from Power Apps:

  • Use the PowerAutomateDesktop object.
  • Call the subflow by its name.
  • Pass inputs as function parameters.
  • Access output values from the returned result.

General syntax:

PowerAutomateDesktop.SubflowName(input1, input2, ...).OutputVariableName;

Example

In this example:

  • The subflow is named GetCustomerData.
  • It accepts a single input parameter. For example, varCustomerId.
  • It returns a value through an output variable named out_customer_data, which is stored in the global variable varResult.

To call the subflow, pass the value of varCustomerId and store the returned output in the varResult global variable:

Set(customer_data_result, PowerAutomateDesktop.GetCustomerData(varCustomerId));

Step 4: Return values to Power Apps

  • Power Automate for desktop returns all values as strings. In Power Apps, cast these values to the appropriate type.
  • When you call a desktop flow subflow, it returns all output variables as a single record value.
  • You can access individual output variables as properties of that record.

Example: Get and use output variables in Power Apps

Set(globalVariable, PowerAutomateDesktop.GetCustomerData(inputVariable))

This example stores all output variables from the subflow in globalVariable.

To access a specific output variable. For example, out_var1:

globalVariable.out_var1

Return complex values

If you need to return complex values (custom objects or lists), return them as output variables and parse them in Power Apps.

  1. In the desktop subflow, build a custom object.
  2. Return the custom object as an output variable.
  3. In Power Apps, use ParseJSON to parse the returned value and access its properties.
Set(parsedValue, ParseJSON(globalVariable.out_customer_data))

Note

Power Automate for desktop returns all values as strings. Before using these values in the app, cast them to the appropriate type (for example, use Value or Boolean).

IntelliSense support

When you call desktop subflows in Power Apps, Power Apps Studio provides IntelliSense to help you discover and use available capabilities.

As you type in the formula bar:

  • The PowerAutomateDesktop object shows available subflow names.
  • Input parameters for the selected subflow are displayed in the correct order.
  • Output variable names are suggested after the function call.

This support helps you:

  • Quickly find available subflows.
  • Understand required inputs without referring back to the desktop flow.
  • Select valid output variables without memorizing their names.

Where you can call a subflow

Invoke subflows from action-capable properties, such as:

  • A button's OnSelect.
  • A control's event property (for example, OnChange) when appropriate for your app design.

Runtime behavior

When the desktop flow runs and execution reaches Run Power App:

  1. The app launches.
  2. The app automatically establishes a communication channel.

The Run Power App action finishes when the user closes the Power Apps window or stops the flow manually.

Limitations and considerations

  • Sequential execution: The process handles subflow calls one at a time. Don't trigger a new call before the previous call finishes.
  • Publishing propagation: After publishing changes to an app, updates might take some time to appear when launching the app again from Power Automate for desktop.
  • Sign-in prompts: In some scenarios, users might be prompted to sign in when the app launches.

Troubleshooting

You can't see the PowerAutomateDesktop object in the Power Apps designer

  • Make sure you use Open app in the PAD action. Then, select Open Designer in the browser and wait until the designer loads the app.
  • Keep the PAD browser page open until it indicates the connection is established.

I can't see my new or updated subflow in Power Apps Studio

  • Reopen the app through Run Power Apps > Open app > Open Designer so the schema refreshes.

Changes to the Power App aren't reflected when running from Power Automate for desktop

  • Make sure you publish your latest changes in Power Apps.
  • After publishing, wait a short period of time before running the app again, as updates might take some time to propagate and become available when launched from Power Automate for desktop. If you don't want to wait, you can relaunch the app by using the Run Power App action to immediately load the latest version.

The app doesn't appear during runtime

Power Apps renders by using the Microsoft Edge WebView2 Runtime.

  • Ensure that WebView2 Runtime is installed on your machine. You can verify this by:

    • Checking the list of installed applications in Windows Settings (Apps > Installed apps), or
    • Running the Power Automate for desktop troubleshooter

  • If it isn't installed, download and install it from Microsoft Edge WebView2.

    On the download page, select Evergreen Bootstrapper and run the installer.

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