As long as I can answer the following questions, should be safe.
And for remixes:
Well at least some Christmas songs are in the public domain 🙂
Issues of Copyright in the thrid world setting.
Further see John Piper’s explaination on copyright.
In light of poverty in the thrid world setting, my view is that people should have access to resources irregardless of wealth – if all they can afford is a handphone. This site offers content free of charge. If there are any issues related to copyright, please contact me at firstname.lastname@example.org.