You've got it backwards, Gears was the zeroth version of the LocalStorage, Web Workers, and Geolocation APIs: HTML5 is based on it It was always an experiment,

You've got it backwards, Gears was the zeroth version of the LocalStorage, Web Workers, and Geolocation APIs: HTML5 is based on it It was always an experiment, a way to test this stuff out without putting it in Webkit or Gecko where people could depend on it. All of the APIs changed form when they were standardized, with some being abandoned (LocalServer and Desktop).