The document describes a study that developed a framework called PTC3 for evaluating educational mobile apps. The framework focuses on pedagogy, technical usability, content, and contextuality. It was developed through a design-based research process involving usability tests with 19 preservice teachers assessing various mobile apps. Their feedback was analyzed to refine the evaluation criteria. The framework can help teachers select appropriate apps and provides implications for integrating mobile learning in teacher education programs and conducting further research.