The similarities above can't be coincidence.

Look at the changes in Secret:

More about the Secret redesign:

http://recode.net/2014/12/18/anonymous-app-secret-unrecognizable-following-overhaul/

Winners and losers of the Anonymous App Wars of 2014:

Losers

While Secret, Yik Yak, Whisper and others reigned this year, a number of others entered the “anonymous social” space this year as well. Few of these still matter.

For instance, a representative sample from the long-tail (data via App Annie):

• TenTwenty, a Yik Yak-like app: dead, buried, and pulled from the App Store.
• Shortwave Messaging, like Secret + FireChat: no longer ranked – meaning it’s ranked lower than #1,500
• WUT, anonymous networking via push notifications: no longer ranked
• Cloaq, anonymous networking: no longer ranked

Winners

And among those who could still be contenders?

They include: Yik Yak, Secret, Whisper, Facebook’s Rooms (if not by traction, but by its parent company’s power to promote it if it chose to), and newly popular entrant After School. To be fair, After School is likely only popular because it had virtually no content protections in place against, and younger users gravitate towards this “wild west” type of sharing experience.

Source: 

http://techcrunch.com/2014/12/18/few-winners-in-anonymous-social-networking-and-secrets-not-one-of-them/

What does the Fox say?