ConquerIons is seeking a definitive solution for the detection of ions in real scenarios by innovatively addressing the limitations of traditional ion-sensing concepts in terms of effectiveness, sensitiveness, robustness and downscaled platforms. The project proposes a new generation of voltammetric, amperometric and optical ion sensors based on calibration-free selective membranes inspired by conventional membranes used in the well-established potentiometry field but with a thickness at the nanoscale. The uniqueness of the dynamic electrochemical tuning of ion-transfer processes across these nano-membranes opens up a revolutionary approach that allows for the monitoring of ion concentration in a sample with unprecedented analytical performance. Thus, the project combines efforts from the synthetic chemistry, material science, nanoscience, electrochemistry and analytical chemistry disciplines resulting in a universal concept for the reliable detection of ions. ConquerIons is based on a research approach carefully designed mainly considering the following challenges: (i) the use of novel materials to afford a robust and universal detection; (ii) the implementation of thin-layer concepts of electrochemical and/or optical-sensing platforms to achieve reduced limits of detection and calibration-free methodology; (iii) the translation of the developed concepts to the single-entity scale (i.e. single nanoparticles) towards the study of ion-transfer processes employing, for the first time, ‘nanocoulometry’ readout; and (iv) exploitation of sensors from the laboratory context based on relevant cases as the next step towards the final use as daily smart informers operating in real scenarios. This latter purpose will lead to a series of extraordinary analytical applications from a long-term perspective related to very distinct fields, such as cell-scale therapies and speciation of trace ion levels in environmental analysis.