Custom Authentication:
1. For OLD Mobile Service - https://azure.microsoft.com/en-us/documentation/articles/mobile-services-dotnet-backend-get-started-custom-authentication/
2. For NEW Mobile App -
keys:
- Turn on App Service Authentication
- Add Microsoft.Azure.Mobile.Server.Login NuGet package
- Create custom authentication endpoint
- Configure service to require authentication
- Use token on client
http://www.newventuresoftware.com/blog/custom-authentication-with-azure-mobile-apps/