This paper introduces and discusses some recent advances in the field of information freshness for Internet of things (IoT) applications. Focusing on a setup in which a large number of transmitters share a common wireless channel to deliver updates to a common receiver, we tackle in particular the role played by random access policies based on variations of the basic ALOHA protocol, employed in most practical IoT systems. The fundamental trade-offs that emerge are discussed together with the

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... ancement achieved by a number of novel schemes tailored to optimize age of information. The article aims to trigger discussion and further research on a relevant yet still largely unexplored field, and highlights some important issues and challenges that have yet to be addressed.