Lollipop was one of the rumour's mill top picks anyway so it wasn't exactly a big surprise. Although at one point, Lion had looked to be a genuine possibility considering that its immediate predecessor was called KitKat.
The biggest change on Android 5.0 is the user interface. The UI now having material design, which is a bold, colorful, and responsive UI design for consistent, intuitive experiences across all your devices. The new material design comes with responsive, natural motion, realistic lighting and shadows, and familiar visual elements make it easier to navigate your device. It also features vivid new colors, typography, and edge-to-edge imagery help to focus your attention.
The new update brings new ways to control when and how you receive messages - only get interrupted when you want to be. You can now view and respond to messages directly from your lock screen. Includes the ability to hide sensitive content for these notifications. For fewer disruptions, turn on Priority mode via your device’s volume button so only certain people and notifications get through. Or schedule recurring downtime like 10 pm to 8 am when only Priority notifications can get through. Incoming phone calls won’t interrupt what you're watching or playing. You can choose to answer the call or just keep doing what you’re doing.
You can also control the notifications triggered by your apps; hide sensitive content and prioritize or turn off the app’s notifications entirely. Android 5.0 brings more intelligent ranking of notifications based on who they’re from and the type of communication. See all your notifications in one place by tapping the top of the screen.
Battery wise, Android 5.0 comes with a battery saver feature which extends device use by up to 90 minutes. It will show you the estimated time left to fully charge is displayed when your device is plugged in and estimated time left on your device before you need to charge again can now be found in battery settings.