ABSTRACTFlexoelectric coupling and flexo-chemical effects can be crucially important for understanding and control of the nanoferroics phase diagrams, electromechanical and polar properties, and soft phonon spectra. Spontaneous flexoelectric coupling in nanoferroics can propose the way to improve and control the nanosystems' physical properties and critical sizes of the size-induced phase transitions by the synergy of flexoelectric effect and chemical strains, as well as it can help to create nanosystems with giant electromechanical response and superior polar properties, which can serve as a source of breakthrough for advanced applications in energy-saving, harvesting, sensorics, information storage and bio-applications. This review can be of interest for the scientists working in condensed matter physics, nano-bio-physics and physical chemistry.