Abundance combined with facile synthesis, easy accessibility to different oxidation states and polymorphs, variety of electronic and magnetic properties, low biotoxicity and natural elimination make of iron oxides a prototype of the ideal functional material. In this research news, we briefly describe some of the fundaments and perspectives of the use of iron oxides in biomedicine, energy storage devices (anodes for lithium ion batteries), photoelectrochemical water splitting and other forms of catalysis.