A challenge when developing against any of the large Social Login providers such as Google is that for security reasons[1], they don't support using http://localhost, which makes doing local application development that uses these providers challenging.

At Hellō, we strive to simplify adding identity to your applications. To enable localhost development, we separated redirect URIs to be either development or production. http://localhost:* and http://127.0.0.1/* are enabled by default for development redirect URIs, but are not allowed for production. Only your team[2] is enabled to flow through development redirect URIs. You can add other development redirect URIs that will similarly be limited to your team.

When you are ready to share your application with the world, add your production URI(s) to your application in the Hellō Developer Console.

[1] An attacker running a local web server on a user's machine can potentially impersonate your application.

[2] Inviting other admins and testers to your team is coming soon!