This document discusses growing an online audience and SoundCloud's experience and strategies for growth. It provides examples of how SoundCloud increased downloads in Brazil by 50% through targeted experiments, decreased signup conversion by 10% through testing landing pages, increased Android downloads by over 40% through referral traffic changes, and increased native app registrations by 30% through app store optimization tests. The key lessons are that SoundCloud achieved growth through insight-informed testing and iteration of targeted, high ROI tactics and calculated bets.