Mac OS X 10.11 El Capitan has been an improvement form its predecessor OS X 10.10 Yosemite. It has gotten some nice upgrades such as Split Screen, Smarter Searches in Spotlight, Safari updates etc. Many persons still prefer Yosemite because of performance. Personally for me, During my experience of using El Capitan. It has proven to be much faster than Yosemite, making it a very fast and efficient OS. Some apps in IOS are updated and only work with OS X 10.11 El Capitan such as Notes. If you try to sync the Notes app in IOS 8 with El Capitan. It will not sync the most recent notes that was created in El Capitan. That could be a reason why persons are not updating to El Capitan (Maybe they are jailbroken on IOS 8) Whats your favorite OS? Mac OS X 10.11 El Capitan or OS X 10.10 Yosemite?