We used a grounded theory approach to investigate and describe the learning of middle school students when they carry out mathematical activities (in the classroom or out of it) and explore mathematical objects and relations using mobile phones. We found that a web of conditions and consequences could be related to the students' learning when they try to utilize the mobile phone features and qualities to explore formal and meaningful mathematical relations individually, or when they collaborate in pairs or groups. The conditions include: the principals' and coordinating teachers' involvement, the activities themes and requirements, the learning modes (in-class, out-of-class), while the consequences protrude the students' control of their learning and the students connecting mathematic with real life and having a different perception of the nature of mathematics. (Contains 1 figure.)