OneSignal Push Notification

Creating one signal app

Login or Signup in https://onesignal.com/

Add an app, Add you app name and click ADD APP

After that select platform and hit NEXT:

Next you need to get Firebase Server Key and Firebase Sender ID. You will get it with Following steps

In another browser tab Open Firebase Console https://console.firebase.google.com and sign in with your Google account.

Press "CREATE NEW PROJECT" or select an existing one below.

Enter a project name and press "CREATE PROJECT".

Go to project OverView

Click Settings -> Project Settings -> Cloud Messaging

Copy server key And sender Id

And Add it in OneSignal app and click SAVE

Select your target SDK PhoneGap, Cordova, ionic and hit NEXT

Copy Your App ID

Add in OneSignal APP ID, Firebase Server Key and Firebase Sender ID in Wordpress -> Mobile App -> Settings

After that Build apk and Subscribe at least one user by launching your app on mobile. Then you need to hit check subscribed user and click DONE

Sending push notification from WordPress

Install OneSignal Push notification plugin and configure according to OneSignal official documents. https://wordpress.org/plugins/onesignal-free-web-push-notifications/

Go to Push-notification menu and wordpress admin and send notification