IoT concept took a part in everyday lives. Environments became smart, suggestive, recognizing, and adopting to its user needs. However, energy efficiency, interoperability, security, and other issues are restricting the number of use-cases and ways the technology can be used. To cope with these issues, cross-layer approach in standard architectures is necessary. This way, information propagating from one layer to the another can significantly influence overall performances—it is necessary to understand and implement all the significant details that may enable and improve specific applications. Moreover, tremendous evolution in data acquisition and transfer is needed to consider efficient hardware and innovative software architectures that still need to be developed to make it a reality. This mostly introduces distributed intelligence for a reliable and effective processing of the information about the physical world that should provide a complete knowledge to the top running applications. These are related to the efficient usage of radio technologies usual referred as in outdoor, indoor, urban, rural environments, its ranges, and battery/battery-less usage. In addition, communication protocols should handle IoT requirements for multiple device, low-power, real-time operations, or satisfying timely consumer needs. Some further challenges involve efficient device discovery schemes, sleep-mode management, application requirements, security issues, or other power constraints. To address these needs, IoT technologies such as Bluetooth Low Energy (BLE), Radio Frequency Identification (RFID), or other outdoor technologies such as LoRa/LoRaWAN, Sigfox, NB-IoT appear to provide a cellular system for IoT devices while transmitting small amounts of data, while going to mmWave in 5G is considered to provide higher bandwidths/throughputs. All of these radio technologies are advancing with aim to satisfy future requirements, there is still the vast space for improvements which require attention from academia, practitioners and industry, standardization organizations, and governments to address these challenges. This special issue accepted 19 contributions that address described problems from many aspects: The paper “Privacy issues of android application permissions: A literature review”, authored by Gulshan Shrivastava, Prabhat Kumar, Deepak Gupta, and Joel J. P. C. Rodrigues provides a survey that deals with the android application permissions that are related security and privacy challenges in Android. It includes various research articles published in computers and security, digital investigation, decision support systems, systems and software security, and information forensics journals in the last 10 years. The survey is based on the following considerations: research issues motivated by the scheme, the methodology used, ability of result analysis conducted, and android features considered for performance evaluation. The paper “Internet of Things feasibility for disabled people”, authored by Nuno Vasco Lopes points out the challenges for designing IoT architectures for people with disabilities. Further-on, it provides a taxonomy for IoT architectures and the IoT requirements when applied to help people with disabilities. Additionally, it also proposes a specific IoT architecture for disabled people that complies with current IoT articles and specifications. The IoT architecture tries to encompass the perspectives of healthcare stakeholders and generic requirements that are necessary for this sort of applications. The paper “A comprehensive survey on semantic interoperability for Internet of Things: State-of-the-art and research challenges” authored by Hafizur Rahman and Md. Iftekhar Hussain presents a comprehensive survey of different semantic interoperability solutions in the context of IoT. The pivotal semantic models available in the literature are compared with the help of a classification framework. This study identifies various open research issues and challenges for facilitating interoperable IoT communications. It also suggest some important tools and frameworks for the purpose of implementation and performance evaluation of various semantic models. After pointing out different prospects and problems of the existing semantic interoperability schemes, the factors for improvement are identified indicating future research directions. The paper “Latency-minimum offloading decision and resource allocation for fog-enabled Internet of Things networks” authored by Qian Wang and Siguang Chen develops a latency-minimum offloading decision and resource allocation scheme for fog-enabled Internet of Things (IoT) networks is developed in this article. It formulates a joint optimization problem of the offloading decision, the local computation capability, and the computing resource allocation of