The potential of a paperless classroom cannot be achieved unless a context is created for collaboration and sharing of paperless content. A class blog is perfect for fulfilling this role. A class blog is free and easy to use and, more importantly, it gives students and teachers the opportunity to create and share paperless content. In addition, most blogs have a comment function, which allows students and teachers to interact with their audience. To capitalize on smartphone ownership and encourage students to participate in real-time conversations, the author experimented with the micro-blogging software, Posterous? Spaces. This paper will share a brief report on experiences using the software at three Japanese universities, describe how students participated on their mobile devices, and reflect on questions and feedback received during the presentation at the 2014 Paperless: Innovation and technology in education conference.