Hidden Things Solution

1. Follow the challenge set up guide.
2. Retrieve the .apk-file from the phone.(see Get Used To Tools - Solution)
3. Execute the following command on the .apk-file java -jar apktool_2.2.0.jar d base.apk
4. Open the values.xml in the AppFolder /res/values/strings.xml
5. Serach for "superhiddenstring"

Please note: Apps use this technique as pat of obfuscatio and/or to hide encryption keys.

If this is done with dex2jar instead of apktool, the values and the manifest would be still encoded and can't be read directly. apktool decodes the manifest and the resources for us.