In the eleventh version (September 2017), it added support for Intelligent Tracking Prevention. The fifth version (June 2010) introduced a less distracted page reader, extension and developer tools it was also the final version for Windows. The third generation (January 2007) brought compatibility to the iPhone via iPhone OS 1, while the Macintosh edition was topped with the fastest browser performance at that time. Safari was introduced within Mac OS X Panther in January 2003, and as of 2021, has progressed through fifteen major versions. It is supported on macOS, iOS, and iPadOS a Windows version was offered from 2007 to 2010. It succeeded Netscape Navigator, Cyberdog and Internet Explorer for Mac as the default web browser for Macintosh computers. It is primarily based on open-source software, and mainly WebKit. Safari is a graphical web browser developed by Apple.