Microbes are an inherent part of life and play an important role in human well-being, to our benefit and to our detriment. Advancements in technology have given us a powerful new tool, microfluidics, which allows us to apply our knowledge of microbes and produce tools that can help us protect and promote our health. Here, I present several approaches using microfluidic technology to build platforms based on three fundamental microbial activities: their growth, their death, and their ability to adapt and mutate. In Chapters 2 and 3, I present the development of platforms for antibiotic susceptibility testing that examine the growth of clinical pathogens under different concentrations of antibiotics to inform us of the best therapeutic choices to fight bacterial infections. In Chapter 4, we discuss the development of a high-throughput platform that leverages the ability of microfluidic platforms to control the physicochemical conditions that determine biofilm removal strategies based on microbial death. Finally in Chapter 5, we miniaturized the adaptive laboratory evolution process and enhanced the oxidative stress tolerance of probiotics based on the ability of microbes to adapt to the changes in their environment. Overall, this thesis shows how microfluidics can be engineered and used to provide real-life solutions and advance the field of applied microbiology