Create Facebook application
1. Goto https://developers.facebook.com , and click 'Log In' on the top right.
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2. If you are not yet logged in to Facebook, you will be prompted to.
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3. If you are not taken directly to the create app page. click on the 'Get Started' on the top right.
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4. On this stage, you should choose the name of your application and enter your email and click Next.
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5. After that, you have to confirm that you are not a robot.
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6. The next step is to select a user role. Choose role which best describes you.
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7. Facebook has many developer 'Products', but the one we want is 'Facebook Login'
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8. Fill in the app 'Display Name' and 'Contact Email'.
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9. Click on 'WWW' to create a web app
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10. For "Site Url', enter https://oauth.io , click 'Save', and click 'Continue'. You can click 'Next' till the end as the other steps shows you Javascripts snippets that you do not need.
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11. You should now see 'Settings' on the left menu, please click on it.
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12. Fill in the 'Valid OAuth redirect URIs' with https://oauth.io/auth
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13. Toggle the switch to make your app public.
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14. In 'App Domains', fill in oauth.io. Note the 'App ID' and 'Secret Key'.
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