iPhone How to login into your Apple ID on the latest iOS virtually/via virtual machine.

[KgHammar]

I have a iPhone 5. I want to download the Google keyboard Gboard. Gets msg ''Cannot Download App..the XX (app/name)..is not compatible with this device. The solution is to login with your own Apple ID to another person's newer device, download the app, then you're able to download a older version of that app later on your older device. Went great until I was asked if I wanted to merge my account with his (and therefore migrate and gather all our mutual files on his device), we chose no. From thereon we got the msg ''Authentication failed'' and loading-wheel just keep spinning. We have checked the password so it's correct. So how do I login to my Apple ID virtually/via a virtual machine, so I can download the app? Is there another workaround?