Amazon Developer

Console

as

Settings
Sign out
Notifications
Alexa
Amazon Appstore
Ring
AWS
Documentation
Support
Contact Us
My Cases

Console

as

Get Started
Design and Develop
Publish
Reference
Support
Skip to main content
React Native for Vega supports Chrome DevTools (CDT) for debugging and profiling Fire TV apps. Use CDT to analyze CPU performance, memory usage, and network activity. The Chrome browser includes CDT, which lets developers inspect, debug, and profile apps. For CDT basics, visit the React Native debugging documentation. This page explains how to set up CDT debugging in Vega Studio for both the Vega Virtual Device and Fire TV Stick.

​
Run your React Native for Vega app

Follow these steps to start debugging:
  1. Open the command palette in Vega Studio: Mac: Shift+Command ⌘+P Linux: Ctrl+Shift+P
  2. Enter Vega App: Run the current Vega app. This command:
    • Starts the metro packager (a JavaScript bundler for React Native)
    • Sets up port forwarding between your device and host computer
    • Launches your app on your device

​
Start CDT

Start CDT from Vega Studio using the integrated debugging experience. Complete the following steps:
  1. Connect your Vega device to your development machine.
  2. In Visual Studio Code (VS Code), go to the Vega Studio panel.
  3. Select your project from the Vega section.
  4. Select Debug from the Build Modes section.
  5. Select a Fire TV Stick device or Vega Virtual Device from the Devices section.
  6. Run your app for debugging. a. Follow the steps in Run your React Native for Vega app. b. Wait for the app to run successfully. c. Verify that the React Native Packager is connected. If the packager doesn’t connect, restart Metro by running Vega App: Run the current Vega app from the command palette again. d. Navigate to the VS Code Output window. e. Select React Native from the drop-down list. Screenshot of a connected React Native packager in the Vega extension.
  7. Launch CDT. a. Open the command palette. Mac: Shift+Command ⌘+P Linux: Ctrl+Shift+P b. Enter Vega: Launch Dev Tools and press return for Mac or Enter for Linux. Screenshot showing where to launch CDT from App Performance Tools. You can also select the Chrome Dev Tools from Vega Studio > App Performance Tools. Screenshot showing a CDT session.
  8. When you start CDT, a progress bar appears in a new window. When loading completes, CDT opens in that same window. The Sources and Console tabs become active, and your app’s JavaScript files appear in the left panel. If CDT fails to connect to the app on your device, you see Disconnected at the top of the window. Screenshot showing a connection error. If CDT disconnects due to Splash Screen display, app restart, or other reasons, close the Dev Tools tab in Vega Studio. Then follow the steps in Start CDT to reconnect.

​
Set a breakpoint or line-by-line debugging

A breakpoint is a designated point in the code where the debugger pauses execution, allowing you to examine the program’s state. Visit Chrome for Developers to learn about breakpoints. Screenshot that shows line-by-line debugging and a paused breakpoint.
  1. In the Sources tab, expand localhost:8081 > index.bundle/ and open the &platform=kepler&dev=true&minify=false file. Search for the function or line you want to debug, then select the line number to set a breakpoint. Screenshot that shows the setting of a breakpoint.
  2. Execute the code in your app. When the debugger reaches the breakpoint, it pauses execution. Screenshot that shows the runtime hitting a breakpoint and pausing.
  3. Inspect the variables or control program execution as normal.

​
Profile app performance

After setting up CDT, use the Performance tab to record a CPU profile or the Memory tab to capture heap snapshots. For guidance on interpreting results, see App Performance Best Practices and Measure App KPIs.

​
Flipper and CDT support

According to the React Native team, React Native 0.74 discontinues support for Flipper. Source maps support in CDT is fully functional in React Native 0.73. This support is available for React Native for Vega when updated to React Native 0.73.
Last modified on July 10, 2026