To be clear, that would technically be:
http://www.iphone.apple The "www" part would remain as it would be part of the world wide web and not another part of the internet.
No. Think about it...is there a site that is just "www.com (http://www.com)?" It would still need to be "www.something.apple"
Well, that's not entirely true.
Based on your comment, then I guess you know about name servers and IP addresses.
A name server translates any DNS name to an IP address. When you type a URL like
http://www.apple.com into your browser, the browser contacts its default name server and asks, "Have you ever heard of www.apple.com?" If this is the first time the name server has heard of
www.apple.com, it finds the .com TLD name server and asks if it knows of the name server handling apple.com.
If so, your name server connects to the name server for apple.com and asks it about
www.apple.com. If the Apple name server has a listing for the www prefix, it returns the IP address for "www.apple.com" and your browser connects to that IP address.
The network administrator for the domain "apple.com" is in charge of mapping the names in the apple.com domain to specific machines and their IP addresses. In many large companies, there will be different machines (with different IP addresses) handling WWW, FTP, Telnet and other traffic. On smaller sites, the same machine can handle everything.
The network administrator makes a list of names and IP addresses,
www.apple.com - 184.85.205.15
IPhone.apple.com - 17.172.224.28 and 17.149.160.28
Support.apple.com -184.85.200.143
The* administrator can put anything in that list, because the name servers don't care. The administrator could put in ilovemicrosoft.apple.com, iLove.google.apple.com, or I.love.microsoft.and.google.com, and when someone types in those names the name server will return the IP addresses associated with them.
In the case of Web sites that happen to work without the "www" prefix, it simply means that the administrator has decided that if there is no prefix, the IP address returned should be the IP address for the Web server.
Therefore, iPhone.apple is valid and would be able to return a valid IP.