I own a app called "who is on my wifi?" which offers a functionality you can guess, giving you list of devices connected to your wifi router.
There is one similar app which is older than mine and own a domain whoisonmywifi.com and claiming that it own a phrase and I can not use them in my app. I have following sub-questions.
Is "Who is on my wifi?" copyrighted?
I have gone through their site but there is no such copyright taken by them, so does just owning a .com domain mean have copyright?