Open source libraries attribution in Android apps [closed]

Question

Several Android apps (especially the ones by Google) feature a section with a list of open source libraries used in the app and for each of them, a full text of its licence. This usually involves the Apache License, which is used in most of the common Android libraries, such as ActionBarSherlock, ViewPagerIndicator, Guava etc.

• Is it mandatory to include such attribution in order to comply with the terms of the (Apache) license?

• How should this section look? If multiple libraries use the same license, is it necessary to duplicate the text of the license for each of them?

• Is it even necessary to include the whole text of the license, or is the sole copyright notice enough (see the appendix here: http://www.apache.org/licenses/LICENSE-2.0)?

• Do the official Android developer guidelines feature some information on this topic (I failed to find any)?

Answer 1

The Apache 2 license does not require attribution in their derived products advertising materials but I in my opinion it is often considered as "a nice thing to do" to support the developers of those libraries.

The attribution requirement "'advertising clause'" was removed in the Apache 1.1 license:

The 1.1 version of the Apache License was approved by the ASF in 2000. The primary change from the 1.0 license is in the 'advertising clause' (section 3 of the 1.0 license); derived products are no longer required to include attribution in their advertising materials, only in their documentation.

Other open source software licenses have different requirements.