"There is no doubt that today we have entered the digital era, and that integrating this reality into mathematics education is no longer an option. ... There is no doubt that this book well reflects the current state of the art in this area ... . I recommend its reading to all those who are interested in technology focused teacher practices and teacher professional development." (Michele Artigue, Educational Studies in Mathematics, Vol. 90, 2015) "It is useful to anyone who wants to get a clear picture of what we know about the uses of technology through the lens of the teacher in real mathematics classrooms ... . It affords reading from multiple perspectives and promises to be a good tool for teacher education and post-graduate courses. It will also serve as an informative basis on which to engage in further research and acquire sensitivity to new contexts and technological developments for mathematics education." (Chronis Kynigos, Technology, Knowledge and Learning, Vol. 19, 2014)