Power Management
Widgets: I found the power management
widget to be
very useful because it shows you right away if high - powered stuff like 3G, WIFI and GPS are ON or OFF, it puts you in (complete but manual) control of the power management.
Notification Centre — One of the most
useful updates to the apps on Mac OS Yosemite is the improved Notification Centre which includes their Today View, which is
very similar to Google Now, in the sense that it allows users to add
widgets like weather, calendar, tasks and many other third party
widgets, as well as pre-installed apps like the
useful calculator.