Despite the huge expansion in recent years of sweat sensing and wearable technologies, several challenges are still open, including poor sample collection, separate sampling and analysis, low multi-sensing capabilities and materials toxicity. In this work, we propose a novel wearable multi-electrode platform efficiently tackling some of these issues. The sensing technology is based on one-step electrodeposited platinum nanostructures to achieve reproducibility and biocompatibility. The platform is highly flexible and includes four electrodes for the simultaneous sensing of analytes, a temperature sensor and a stable reference electrode (RE) with an ionic-liquid junction. A low-cost cotton fluidics is designed to continuously bring fresh sweat to the sensing area, while disposing the already-tested sample. The excellent analytical performance of the proposed technology is proved for different applications: Li+ for Therapeutic Drug Monitoring (TDM) in psychiatric disorders, Pb2+ for the control of heavy metal contamination, K+ and Na+ for sport tracking. The sensors offer linear responses in artificial sweat in the ranges of clinical interest. A simulated wearable setup on a mannequin is used to test reversibility and selectivity. Finally, potassium and sodium are successfully tracked on five human volunteers during physical exercise. The accuracy of the in-situ measurements is demonstrated (Pearson coefficients of 0.97 and 0.81 for Na+ and K+, respectively). With its high biocompatibility, selectivity and accurate sample-handling, this wearable platform represents an important step towards the development of non-invasive monitoring devices for m-Health, paving the way for a better understanding of physiological parameters and clinical needs of each individual.