To create a Facebook App, go and visit: https://developers.facebook.com/apps/
Click on the “Create App” button. A Popup will appear.
From that Popup Select “Manage Business Integrations” option and hit “Continue” button.
Note: You need to use a personal Facebook Account for creating an App. A business account won’t work. Your personal account needs to be a verified Facebook account. If your account isn’t verified yet, you’ll receive a text message from Facebook to verify your account. So make sure, that you have a mobile number set within your account, otherwise you won’t be able to create an App.
Enter the App Display Name and the contact email and click the “Create App ID”.
Now it will redirect to the “Add Product” page and in this page click the “Set Up” button in “Facebook Login”.
Click the “Web” button.
In the “Site URL” section add your Website URL and save it.
Note: If the “Quickstart” page is blank and you cannot enter the domain url, please go to “Settings > Basic” section, just below the Dashboard and then click the “Add Platform” as shown below.
Then select the “website” as given below.
In this page you can add the Website URL and save it.
Click on the “Facebook Login > Settings” link as shown below. Here enter the “Valid OAuth redirect URIs” and save the changes.
Valid OAuth Redirect URL is https://api.wpautorepublish.com/auth/facebook.
The app is ready now. Click the “Settings > Basic” link in the menu to see the app id and secret.
Here the app is in development mode. Only the developer can view the posts now.
We need to “submit the app for approval” and after the app get approved, we can make the app public and the users can see the posts in the facebook.
The App Review Process Submission is given below.
You can now use the Facebook app keys in the plugin. Now enter these keys in the plugin settings in your site. After entering the keys in the Facebook popup dialog box, you need to “Authorize” the account. You can see the FB pages in the settings page only after authorizing FB account. When you click on the “Verify” button, it will redirect to a Facebook popup dialog box.
Note: If you are doing group posting, you have to add your Facebook app within that group on which you are posting. Follow the steps mentioned in the link here.