Do I need to enter my email as Apple id on my older device
Do I need to use my email address as Apple id on my iPhone X
iPhone X
You can use any one of your email addresses for use as your Apple ID. You do not have to use an Apple ID on your iPhone, however, several important features will not work if you are not signed in with an Apple ID. The short answer to your question is a YES you should.
Axel F.