In this paper two different photonic lab-on-a-chip devices for real-time cell screening are presented. We discuss, in parallel, screening of cell viability and cell count using a multiple total internal reflection (MIR) system, and a microbioreactor (MBR) for continuous cell culture screening. Each device takes advantage, in different ways, of the enhanced light-analyte interaction provided by the full-field approach. Their performance and how they represent an improvement to current methods, are also discussed herein. Both devices integrate photonic components and are fabricated by soft lithography (PDMS) replica molding of SU-8 masters, thus making them low-cost and easily mass produced.