OneSignal integraton
OneSignal is a high volume and reliable push notification service for websites and mobile applications. To know more about onesignal follow this link -
Add App Name
Select Google Android(GCM)
Generate Google Server API key
Follow this link to configure onesignal in your app

Place your OneSignal App ID in build.gradle(Module:app) file in the project

manifestPlaceholders = [onesignal_app_id : "e6f3475b-4aad-4ea4-ab00-4386c19a4863",
// Project number pulled from dashboard, local value is ignored.
onesignal_google_project_number: "REMOTE"]
Replace your generated google-service.json inside App Directory in project
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