<uses-library /> in Android Manifest

<uses-library> is not meant to include libraries in your application. It is used to restrict app availability in Google Play based on the availability of a library already on the device like maps. AndEngine is a library project so include it in your build via Ant, Maven or whatever IDE you use.

In case you aren't familiar with what a library project is here's a link:

https://www.vogella.com/tutorials/AndroidLibraryProjects/article.html

If this element is present and its android:required attribute is set to true, the PackageManager framework won't let the user install the application unless the library is present on the user's device.

<uses-library> - specifies a shared library that the application must be linked against. This element tells the system to include the library's code in the class loader for the package.