Single-crystalline materials play a crucial role in the modern semiconductor electronics industry and fundamental science. The ability to grow large single crystals with high purity and low concentration of defects allows us to build new types of devices such as high-resolution semiconductor radiation detectors. Another important application of crystals is fundamental research, where crystal growth enables rapid screening of phase diagrams, structure determination and property characterization of new compounds. This presentation covers both aspects, first outlining present challenges and advances in semiconductor radiation detection and growth of large single crystalline ingots of CsPbBr3. The second part describes several cases of exploratory crystal growth using hydrothermal and flux techniques, which were used to synthesize new magnetic U(IV) fluoride phases and a novel class of layered chalcogenides that can undergo reversible single-crystal-to-single-crystal hydration. These examples show that crystal growth is a versatile tool that promotes new functional materials discovery and their large-scale growth for device fabrication.