Mozilla has launched an ambitious new project aimed at breaking down the proprietary app systems on today’s mobile devices. The project, dubbed WebAPI, is Mozilla’s effort to provide a consistent, cross-platform, web-based API for mobile app developers. Using WebAPI developers would write HTML5 applications rather than native apps for iOS, Android, and other mobile platforms.

Mozilla isn’t just talking about WebAPI, it’s already hard at work and plans to develop the APIs necessary to provide “a basic HTML5 phone experience” within six months. After that the APIs will be submitted to the W3C for...