Lidderbuch is an app of the ACEL, the umbrella organisation of over 40 luxembourgish student organisations in Europe and USA. It unites songs traditionally sung by the students. Over 80 lyrics texts have been collected and prepared for this.
All contents of this app is available offline.
This is an OpenSource project under the MIT license:
https://github.com/AcelLuxembourg/LidderbuchApp