This chapter primarily describes and discusses students' learning of mathematics outside the classroom because this learning was enabled by the special features of cellular phones as learning tool. It also examines students' learning of mathematics inside the classroom using cellular phones. In this learning, students investigated mathematical concepts and discovered mathematical relations. The chapter addresses three learning aspects: students' learning behaviour with cellular phones, their perceptions of learning with cellular phones and their learning emotions in that environment. The first study by Wajeeh Daher in 2010 examined middle students' behaviour when building their mathematical knowledge in the cellular phone environment, while the second by Nimer Baya'a and Daher in 2010 examined the conditions and consequences of students' studying outdoors to investigate real-life phenomena mathematically. The third study by Daher in 2011 found that the cellular phone outdoor environment in which students work on everyday life activities was appropriate for cultivating mathematics students' positive emotions.