One of the key complexities of the ecosystem is the mobile handset and wireless carrier component of the landscape. In addition to the hardware diversity, the variety of operating systems on these devices continues to grow. There exist vulnerabilities related to specific mobile device manufacturers and operating system (OS) versions. Attacks on devices can come in many forms, from malware to social engineering, theft or physical loss of the device, or improperly secured devices either through misuse or by users jail-breaking their devices. The most apparent security concern is protecting personal data (payment account numbers, PINs, security codes, passwords) that are either stored in or flow through a mobile device. Trusted execution environments (TEEs) are being increasingly recognized as a key component for the deployment of sensitive applications, such as digital content protection, enterprise services, or financial services. TEE provides a way of enhancing the security of mobile devices and executing sensitive operations on devices running standard operating systems.