Apple begins testing OS X 10.11.1 with focus on stability, compatibility and security Posted on September 17, 2015 By admin Before OS X 10.11 El Capitan launches to the public, its first forthcoming maintenance and security update is already available in beta form for developers to test. AppleInsider – Frontpage News Apple Tags:10.11.1, Apple, begins, compatibility, focus, Security, stability, Testing