Email became one of computing's most durable interfaces because it was the only truly universal platform available—developers used it to distribute software, manage tasks, and control systems without needing to build separate apps or support multiple operating systems. The article traces how this hack, from 1985's Netlib to modern tools like Trello and Readwise, persists because email solved a real problem: letting users interact with software without friction or commitment.

• Netlib (1985) distributed mathematical software via email commands, hitting 4,000 downloads monthly—proof that email worked as a functional app store before the web existed.
• Email eliminated platform fragmentation: when developers faced supporting Unix variants, Mac, Windows, and other systems, email offered a single interface that worked everywhere.
• The pattern stuck because email solved two sides of the problem simultaneously—users didn't need new accounts or apps, developers didn't need to build separate interfaces for each platform.