I have a business requirement to allow SharePoint 2016 Site reachable from iOS/Android SharePoint Mobile Application. I have setup a new Web App and extended and published it over the internet, I can open the Web Page just fine from any device including browsers in the mobile phone. However, when I attempt to connect to the service via the Mobile App, I am able to authenticate using NTLM authentication, however all I see is a blank loading page.
Is there any recommended way to implement SharePoint Web App so it is useable from the mobile app? Also I have read that the application only supports NTLM and FBA authentication, have any of you tried to implement FBA with multifactor authentication and used it with the app?