“…These R&D activities are typically related to conceptualization, product and process innovation, concept adaptation to satisfy a specific application, performance assessment, upscaling, and more [20e22]. Notably, the (bio)sensing assay, including the (bio)sensing element, the transducer, and the smartphone-based detection, should all undergo extensive validation regarding the targeted application [23,24]. Additionally, all stages of SbS operation should be developed with the end-user in mind; for instance, if the device has been designed for use by a nonexpert outside of a laboratory, any necessary sample preparation or collection steps should be as straightforward, fast, and as robust as possible [25].…”