In reference to your question why Yik Yak... why Gossup?
Why not create an app similar to what they are but integrate features like Twitter and Instagram? This is Chattur.
http://www.theatlantic.com/magazine/archive/2014/12/the-fall...
There is only one developer behind Chattur.
Do you complain about how simple Yo's website is? http://www.justyo.co/
I feel that if you would like to learn about the app you can check it out on the App Store / Play Store.