This document outlines 20 ideas for using mobile phones in the language classroom, as well as some potential problems. Some of the ideas include using the phone's notes, camera, and voice memo features to collect language samples from everyday conversations and media. Other ideas involve using text messaging for vocabulary reinforcement, circular writing, and tandem learning. Additional ideas are using the phone for blogging, microblogging on Twitter, social networking, language exchanges, and distributing listening and reading materials. The document also lists some potential problems like lack of access to phones, cost, noise disruption, privacy issues, and increased teacher workload. It concludes by arguing that since most students have phones, teachers should take advantage of the technology in their classrooms.