Abstract: The rapid development of the Internet of Things (IoT) requires systematic development methods that address complex functional, architectural, and validation concerns. This review synthesized research published between 2016 and 2023 to characterize common functional requirements (FRs), current modelling techniques, and validation practices. From an initial corpus of 1,598 articles, 425 publications were selected for in-depth analysis. The results demonstrated a consistent emphasis on data handling, inter-device communication, analytics, and system management. Nevertheless, critical gaps persisted in end-to-end security and context-aware computing. Sequence, class, and use case diagrams dominated modelling practices, which indicated attention to system behavior and interactions. Conversely, state machine and deployment diagrams were underutilized despite their potential to better capture runtime states and architectural configurations. The validation approaches in IoT development were primarily empirical, with experiments and case studies predominating. Expert reviews are valuable for early-stage assessment, but were rarely applied, which indicated missed opportunities for early improvement of design quality in the lifecycle. Overall, the results reflected the maturity and limitations of current practices in IoT engineering. These limitations can be addressed by diversifying modelling techniques, enhancing security integration, and using hybrid validation frameworks. This review presented a foundational reference to guide the systematic development of scalable, secure, and context-aware IoT systems, and contributed to the evolving body of IoT software engineering knowledge.

Nor Haniza Ramli, Nur Atiqah Sia Abdullah and Nur Ida Aniza Rusli. “A Systematic Review of Functional Requirements, Modelling Practices, and Validation Strategies in IoT Application Development”. International Journal of Advanced Computer Science and Applications (IJACSA) 16.12 (2025). http://dx.doi.org/10.14569/IJACSA.2025.0161210

@article{Ramli2025,
title = {A Systematic Review of Functional Requirements, Modelling Practices, and Validation Strategies in IoT Application Development},
journal = {International Journal of Advanced Computer Science and Applications},
doi = {10.14569/IJACSA.2025.0161210},
url = {http://dx.doi.org/10.14569/IJACSA.2025.0161210},
year = {2025},
publisher = {The Science and Information Organization},
volume = {16},
number = {12},
author = {Nor Haniza Ramli and Nur Atiqah Sia Abdullah and Nur Ida Aniza Rusli}
}