Numeracy achievement of Australian school children is a national priority according to the Australian Curriculum. There is increasingly compelling evidence that numeracy needs to be a focus in all curriculum areas, not solely in mathematics (Human Capital Working Group, 2008). At the same time, there is an ever-increasing scope for the use of mobile technologies to enhance learning and teaching. This article examines how numeracy and mobile learning work together as teachers in the Middle Years are mentored to use iPad applications (apps) effectively within their own curriculum area to enhance the learning of numeracy for children in their classes.