AppBlock was built by a Czech developer who had a personal productivity problem: he kept opening social media apps when he was supposed to be working. He built a simple solution for himself, published it on the Play Store, and discovered that millions of other people had the exact same problem.
What makes AppBlock instructive is what it did NOT do. It did not add social features (accountability partners, shared blocklists). It did not add AI-powered focus recommendations. It did not build a web version. It did not pivot to B2B. It did not raise venture capital and hire a large team. It stayed focused on the one thing it was built to do: block apps on a schedule, reliably.
The business model was equally simple: free tier with basic scheduling, paid tier (AppBlock Pro) with advanced scheduling, profiles, and crisis blocking (a feature that makes it impossible to turn off blocking without significant friction, for people who know they will cheat otherwise). The paid tier conversion was strong because users who needed the paid features needed them badly — they were not optional enhancements but necessary tools for people with serious distraction problems.