While the documentation itself is available to you under the Apache 2.0 license, note that proprietary trademarks and brand features are not included in that license. Google's trademarks and other brand features (including the Android stylized typeface logo) are not included in the license. https://source.android.com/license.html

Android is a proprietary trademark wholly owned by Google.

See also: Leverage over manufacturers https://en.wikipedia.org/wiki/Android_%28operating_system%29...