The digital revolution has come to microfluidics. In digital microfluidics (DMF), discrete droplets are manipulated by applying electrical fields to an array of electrodes. In contrast to microchannels, in DMF each sample and reagent is individually addressable, which facilitates exquisite control over chemical reactions. Here, we review the state‐of‐the‐art in DMF, with a discussion of device formats, actuation physics, and biological and nonbiological applications. Along the way, we identify the key players in the field, and speculate on the advances and challenges that lie ahead. As with other fronts in the digital revolution, there have been and will be unexpected developments as DMF matures, but we posit that the future is bright for this promising technology.

Digital microfluidics has become a popular tool for biochemical and biomedical applications. However, its current format is restricted to actuation of droplets on a single plane. Here, we introduce a new method for fluid handling on flexible devices, which we have termed all-terrain droplet actuation (ATDA). We show that ATDA can be used to manipulate droplets across a wide range of geometries, including inclined, declined, vertical, twisted, and upside-down architectures. These new geometries enable flexible, straightforward integration of distinct physicochemical environments on monolithic devices. To illustrate this capacity, we developed temperature- and oxygen-sensitive colorimetric sensors, as well as an automated method for selective enrichment of DNA from a heterogeneous mixture. We anticipate that ATDA will be a useful new tool in the growing trend toward laboratory miniaturization.

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