POPULARITY CONTEST: Apps in the education category have risen from 2% to 6% of the top mobile apps in recent weeks. The arrival of a new school year may explain some of the bump--but why are some apps doing especially well? CB Insights checks out which venture capital-backed apps are gaining traction, tracing the ascent in popularity of Duolingo, Edmodo, Classdojo, Schoology and Remind (now in the Top 5 free apps).
