In the last decade, metal-halide perovskites (MHPs) have grown to the most promising material classes for future photovoltaic (PV) devices. While their huge potential is out of question, recent experimental and computational research expands beyond the class of leadhalide perovskites exploring chemical and structural phase spaces of MHPs and perovskites derivatives. Several structural diverse systems are now under investigation, including, for example, 3D, 2D, and double perovskites, targeting applications beyond PV, as e.g. photodetection and photocatalysis. The expansion of the discovered material space of MHPs has recently moved towards the investigation of lead-free systems in order to overcome the concerns related to Pb-toxicity.