Android is mostly Apache licensed.  Meaning OEMs don&#x27;t have to publish their changes.<p><a href="http:&#x2F;&#x2F;source.android.com&#x2F;source&#x2F;licenses.html" rel="nofollow">http:&#x2F;&#x2F;source.android.com&#x2F;source&#x2F;licenses.html</a>