Smartphones functionalities resemble more and more those of personal computers. Smartphones incorporate high data rate internet connections, information organization applications and digital rights management (DRM) agents. This paper describes an extensible secure architecture for smartphones. Sensitive data storage facilities, cryptographic engines, and physical protection mechanisms such as debug port access control are presented. The described secure architecture is a part of Freescale Mobile Extreme Convergence (MXC) architecture and i.MX application processors family, and can be embedded in a wide range of smartphone or Personal Digital Assistance (PDA) products.