It just seems a bit melodramatic. Should Google Mail have been named Google Post, just because Yahoo Mail was first? They aren't operating in the same space; furthermore, Facebook didn't name it just "Paper" in the App Store, they've named it "Paper - stories from Facebook".
I do not know - there are 240 apps in Google Play store that have "paper" in name. This includes "Draw Paper", "Paper Draw ", "White Paper", "Infinite Paper" and countless others. Also at least two apps are just called "Paper" - not sure how anyone can distinguish them other than looking at company name.
I seriously doubt that 53 was the first company that used Paper in the name.
I don't know what you mean there is "Paper – stories from Facebook" and "Paper by FiftyThree". You know what I don't see them complaining about? "Paper" by misoft (an identical product by the way) and 100 other apps with paper in the title. Considering misoft got "paper" and fifty three had to use "Papaer by FiftyThree" it kind of makes me wonder if this isn't a case of the pot calling the kettle black.
This seems much more like manufactured controversy for free press than anything else.