The development of nanoporous materials has gained significant attention due to their unique structural properties and multimodalities, which are highly relevant for advanced sensing technologies. The capability to directly grow nanoporous materials on flexible substrates or indirectly integrate them into soft templates through mixing and dispersion opens exciting opportunities for a new class of flexible and stretchable electronics for personalized healthcare applications. This review paper provides a snapshot of recent advancements in flexible nanoporous materials and their applications, emphasizing biological and biomedical sensors. The review highlights the material of choice for flexible and stretchable substrates and effective approaches to synthesize and integrate nanoporous architectures onto soft polymers. Applications from wearable sweat sensors, mechanical sensors for electronic skins, implantable bioelectronics, and gas sensing are also presented. The paper concludes with current challenges and future perspectives within this highly active research paradigm.