For a SharePoint public facing website when anonymous users tried to access the site through mobile devices, users were getting authentication prompts.
The public facing site was created based on “Team site” Template.
It has been observed that users were being redirected to a layouts page at /_layouts/mobile/mblwp.aspx. It seemed to be this page that was returning a 401 error and prompting for authentication.
By deactivating “ViewFormPagesLockDown” feature site open up in mobile view.
Once this command is executed, re-apply anonymous setting again and now site accessible through mobile device.