Calendly

Tope Awotona was frustrated. He spent half his time scheduling meetings through email chains. Someone had to coordinate time zones, suggest options, wait for responses. The process was broken but everyone accepted it. He built Calendly to solve his problem: let people pick a time slot instead of wasting weeks confirming. The tool worked so well he decided to share it. Awotona bootstrapped Calendly with his life savings. He couldn't afford advertising. Instead, every meeting invite using Calendly included branding and a link. When someone received a Calendly invite, they saw the product and often created accounts. The product spread because usage was distribution. Every user became an unpaid salesperson recruiting the next customer.