  Control over the amplitude, phase, and spatial distribution of
visible-spectrum light underlies many technologies, but commercial solutions
remain bulky, require high control power, and are often too slow. Active
integrated photonics for visible light promises a solution, especially with
recent materials and fabrication advances. In this review, we discuss three
growing application spaces which rely on control of visible light: control and
measurement of atomic quantum technologies, augmented-reality displays, and
measurement and control of biological systems. We then review the commercial
dynamic surfaces and bulk systems which currently provide visible-light
modulation and the current state-of-the-art integrated solutions. Throughout
the review we focus on speed, control power, size, optical bandwidth, and
technological maturity when comparing technologies.
