What is "material-design"

Design material, introduced with the Lollipop version (Android 5.0 - API21), is a comprehensive guide to visual, motion and interaction design for various platforms and devices.

It incorporates new concepts and ways to develop and "be" Android:

• A new theme.
• Widgets for cards and lists.
• Custom shadows and crop views.
• Drawables vector.
• Custom animations.

Follow the guidelines described in specifications of Material Design and use the new components and functionalities available from Android 5.0 (API21).