  The lead halide perovskites demonstrate huge potential for optoelectronic
applications, high energy radiation detectors, light emitting devices and solar
energy harvesting. Those materials exhibit strong spin-orbit coupling enabling
efficient optical orientation of carrier spins in perovskite-based devices with
performance controlled by a magnetic field. Perovskites are promising for
spintronics due to substantial bulk and structure inversion asymmetry, however,
their spin properties are not studied in detail. Here we show that elaborated
time-resolved spectroscopy involving strong magnetic fields can be successfully
used for perovskites. We perform a comprehensive study of high-quality
CsPbBr$_3$ crystals by measuring the exciton and charge carrier $g$-factors,
spin relaxation times and hyperfine interaction of carrier and nuclear spins by
means of coherent spin dynamics. Owing to their "inverted" band structure,
perovskites represent appealing model systems for semiconductor spintronics
exploiting the valence band hole spins, while in conventional semiconductors
the conduction band electrons are considered for spin functionality.
