Using behavioral psych tricks to design engaging products.
Chat with native speakers in your target language.
Why hasn't this been made yet? EDIT: They did it, a year after this post.
Creating music moments (Product School final project)
A Product School design sprint.
Now I can finally stop having to apologize for Ultimate Guitar.
"Pineapples don't act like people...Literally all they do is take tests, I haven't programmed them to do anything else."
"Liquor delivery services, robotic bartenders, and smartphone breathalyzers..." might be of interest to the STROTW crew.
"We don't take kindly to your kind around here" really isn't a valid excuse anymore, Indiana.
No need for extra bells and whistles - these just make sense.