The new Icelandic app, QuizUp, reached one million downloads on Friday — just eight days after being released.
Business Insider compiled a report of 15 hot startups and how long it took them to reach one million users, downloads or sales. The list includes social media sites like Twitter, which took 24 months to reach its one millionth user and Facebook, which took ten months.
Mobile photo sharing app Instagram reached its one millionth milestone in under three months and currently has over 11 million users. The mobile social network app Path, which was launched in November 2011 received over one million downloads within its first two weeks.