Mathematical applications (apps) are becoming commonplace in educational settings. Despite their increasing use, limited quantitative research has been undertaken that might support teachers in making appropriate pedagogical decisions regarding their use, nor how teachers might go about selecting appropriate apps from the multitudes available at iTunes or Google Play. This chapter explores how cluster analysis can be used to identify homogeneity among elements within apps, thus assisting teachers to make decisions regarding which apps might be most appropriate. Based upon selection criteria and rankings generated via a number of scales, the cluster structure of 53 apps to support geometry learning in elementary mathematics classrooms is reported. The chapter concludes by exploring the homogeneity and heterogeneity of these clusters of apps and suggests how to use these apps to enhance student mathematical learning.