# Customize existing sample applications Source: [https://docs.qualcomm.com/doc/80-70015-51/topic/customize-sample-applications.html](https://docs.qualcomm.com/doc/80-70015-51/topic/customize-sample-applications.html) To modify the sample applications, use the `devtool` utility from the eSDK to get the source code for sample applications. After making the required changes, use the `devtool` utility to compile and package the applications into an installable format (`ipk`). Download and compile the existing sample application using the `devtool` utility of Yocto. 1. Download the source: 1. Go to the directory where the eSDK was installed: cd Copy to clipboard In the command, `` is the file system path where the eSDK is installed. 2. Set up the source environment: source environment-setup-armv8-2a-qcom-linuxCopy to clipboard 3. Download the sample application sources: devtool modify qcom-gst-camera-single-stream-exampleCopy to clipboard The command `devtool modify` initializes the workspace and downloads the sample applications from the repository. The sources are at <workspace\_root>/workspace/sources/qcom-gst-camera-single-stream-example. 2. Build the application: 1. After you do the necessary customizations, run the following command to recompile: devtool build qcom-gst-camera-single-stream-exampleCopy to clipboard Note: The devtool reset is necessary whenever there is any modification to the source code and recipe file: devtool reset qcom-gst-camera-single-stream-exampleCopy to clipboard 2. Generate an installable IPK file: devtool package qcom-gst-camera-single-stream-exampleCopy to clipboard The installable packages are at <workspace\_root>/tmp/deploy/ipk/armv8-2a/. 3. Install the updated application: 1. Push the application on the target device: opkg --force-reinstall install <.ipk that was generated >Copy to clipboard For example: opkg --force-reinstall install qcom-gst-camera-single-stream-example_1.0-r0_armv8-2a.ipkCopy to clipboard **Parent Topic:** [Develop applications](https://docs.qualcomm.com/doc/80-70015-51/topic/application-development.html) Last Published: Jan 23, 2026 [Previous Topic Develop your first application](https://docs.qualcomm.com/bundle/publicresource/80-70015-51/topics/content-develop-your-first-application.md) [Next Topic Troubleshooting](https://docs.qualcomm.com/bundle/publicresource/80-70015-51/topics/troubleshooting.md)