Display omitted •Applications and current trends in the chemistry of POMs were summarised.•Novel strategy to form advanced multifunctionalized POM clusters was presented.•The need to develop POMs and their applications is demonstrated. This paper reports the most interesting applications of polyoxometalates (POMs) over the last five years, highlighting the relationship between their complex nature, properties, and chemical structure. POMs are a well-known class of metal–oxygen nanoclusters with tunable size and structure. Owing to their various properties, they have attracted great attention in the fields of current socioeconomic interest, such as materials science, catalysis, hydrogen production, environmental protection, and advanced medicine.The role of the characteristic structure of this class of compounds and the role played in the apllications discussed have been emphasised.