Berlin-based 6Wunderkinder is adding more features to its new Wunderlist Pro paid tier of service today, answering the number one request of its users with the addition of file upload and sharing. Use
Wunderlist has been an to-do and GTD app staple since its launch back in 2010, but 6Wunderkinder, the company behind it, has always given away its products free of charge, free of advertising and avai