Appcelerator has taken the beta tag off its open source Titanium development kit, a means of building native desktop and mobile applications using traditional web-development tools such as JavaScript, Python, Ruby on Rails, html, and CSS. Titanium 1.0 was officially released today, with the Silicon Valley–based startup claiming significantly improved performance on iPhone and Android handsets after reconstructing the kit's mobile setup. In beta, Titanium built its native iPhone and Android applications by way of the WebKit browsers built into those high-profile mobile platforms, but after a three-month rewrite, it now bypasses the browser entirely, according to director of marketing Scott Schwarzhoff.