A simple start for android programming.

android在java层面操作底层系统的源代码，并包含各个硬件的参数，作为编程开发需要了解底层知识的人非常有用-android in the the java level of the source code of the underlying system operation, and contains various hardware parameters, programming developers need to understand the underlying knowledge

iBeacon for android programming. It is very simple to use.