Mobile Learning is a new paradigm of Technology-enhanced Learning in full alignment with the key objectives of the 21st Century Education and Training. Wireless and Mobile Devices, widely available nowadays, are exploited to allow anyone to access and interact with digital and learning resources from anywhere, at anytime and with a variety of devices. On the other hand, Language Learning is a top priority area of the new framework for European cooperation in education and training, recently adopted by the Council of Education Ministers of the European Union and can benefit the most from these developments. In this context, the MW-TELL Project addresses the needs of the emerging mobile-supported training services for the provision of on-demand Lifelong Language Learning, beyond time, place and device restrictions.