Language-learning app Duolingo raised $30 million in a Series F funding from Alphabet's CapitalG. Post the investment, Duolingo's valuation stands at $1.5 billion. At present, Duolingo's total funding comes to $138 million with investments from Ashton Kutcher and Tim Ferriss, among others. It is now the first Pittsburgh-based tech startup valued at more than $1 billion.