Why are my Android push notifications working in debug mode but not in the release build?

This issue commonly occurs when there is a configuration difference between your debug and release builds, most often with the package name (also known as applicationId in your build.gradle file).

Push services like Firebase Cloud Messaging (FCM) are configured to send notifications to a specific, unique package name. If your release build generates a different package name than the one configured in your Firebase project and Pushwoosh control panel, the device registration will fail, and notifications will not be delivered.

How to Troubleshoot and Fix

1. Inspect your build.gradle file: Check if your buildTypes block specifies a different applicationId or adds an applicationIdSuffix for debug builds. This is a common practice to differentiate between build types.

   Example build.gradle configuration:

   android {
     ...
     defaultConfig {
       applicationId "com.yourcompany.yourapp"
     }
   
     buildTypes {
       debug {
         // This suffix changes the final package name for debug builds
         applicationIdSuffix ".debug"
         ...
       }
       release {
         // The package name for release builds remains "com.yourcompany.yourapp"
         ...
       }
     }
   }
   

2. Verify Firebase/FCM Configuration: Go to your Firebase project settings. Ensure that the package name registered for your Android app is the one used for your release build (e.g., com.yourcompany.yourapp from the example above).

3. Check Pushwoosh Settings: In your Pushwoosh control panel, navigate to your application's configuration page and confirm that the Android Package Name field exactly matches your release build's package name.

4. Perform a Clean Installation: After you have verified and corrected any configuration mismatches, you must completely uninstall the app from your physical test device and then perform a fresh installation of the release build. This forces the app to re-register for push notifications with the correct settings.