Since I have experienced the use of cellphones in the classroom first hand, I think it is a good idea, for the most part. During my practicum, on the recommendation of my sponsor, I always allowed my English Language Arts students to take photos of the overhead of notes or the vocabulary that I had assigned for homework or for a quiz. Students can sometimes be slow in taking notes or they miss the notes because they are participating in class discussions. On the other hand, as Susan Bearden states, students cannot pay attention and participate in class discussions as much when they are focusing on note-taking. This inevitably affects their learning.
In the language classroom, however, that might not be really conducive to learning, since learning a language implies learning how to write as well as learning how to speak. Students need the practice that comes with writing in order to learn a language properly. Using mobile devices to check the meaning of vocabulary or to remind oneself about homework is a good idea, nevertheless. And although I agree with the author about the multiple possibilities for using mobile devices in different study areas, we also need to monitor closely if students are using them for learning purposes or if they are just using them for socializing with their friends during class. Setting "clear parameters" for mobile device use is a good idea, however, that does not guarantee that students will not use them inappropriately.