The G-CAPodes' ability to switch reversibly the capacitance depending on the gate bias is a highly valuable feature for various applications where a fast tuning of the capacitance is needed e.g. in the field of radio frequency circuitry, signal processing, and filtering, as well as digital to analog conversion. In electronics, the varactor diode represents a variable capacitor in which the width of the depletion layer in the p-n junction of the diode (acting as the dielectric separator between the conductive contacts) can be controlled allowing to adjust capacitances usually in the range of 3 to 300 pF. Another variant are varactors based on the metal oxide semiconductor field effect transistor (MOSFET) architecture (source, drain, and gate contacts). The inversion mode (I-MOS) varactor is a special type of MOS varactor demonstrating sigmoidal-shaped C-U curves (Figure ). The curve and the threshold voltage (Vth) can be shifted to higher or lower bias potentials depending on the applied controlling potential (UC) to the body of the I-MOS. The G-CAPode exhibits a C-U characteristic, 3-electrode architecture, and switching characteristics depending on the gate bias akin to an I-MOS varactor. Compared to the semiconductor-based I-MOS device, the G-CAPode can achieve way higher capacitance values and represents a silicon-free alternative with a function principle based on ions instead of electrons. Therefore, the G-CAPode could pave the way for designing silicon-free alternatives with low toxicity, flexibility, and biocompatibility for ion-based computing and signal processing in particular promising for applications in the field of wearable, flexible hybrid electronics and sensors. The G-CAPode is expanding the previously reported super-varactor concept based on the CAPode device allowing for reversible switchability and control of the C-U curve depending on the applied bias voltage which was not achievable before.