This book focuses on the impact of secure frontend devices for the Internet of Things (IoT). It explains how to identify vulnerabilities of IoT applications and how to protect them against misuse and attacks. Provided insights will help readers to design a reliable and trustworthy IoT ecosystem ensuring a high level of user confidence and a fruitful deployment. As a starting point, the book provides guidance how to identify risks and potential threats. Then, it explains which countermeasures are available and introduces all major ingredients for an efficient implementation of IoT security measures, e.g. a bullet-proof protection of user privacy and device identities. The author outlines an efficient design approach that combines classical embedded computing with smartcard technology and wireless cellular networking like LTE-M or NB-IoT. The target audience includes industrial professionals and students focusing on low cost design and a fast time-to-market. The book is ideal for engineering-minded IoT project owners to safeguard their business goals.