Used as a moisture indicator in silica gel desiccants, where it changes color from blue (dry) to pink (hydrated), providing a visual cue for humidity levels. Commonly employed in humidity-sensitive packaging to protect electronics and pharmaceuticals.

Also used in electroplating baths to deposit cobalt metal for wear-resistant and corrosion-resistant coatings with a shiny finish.

Serves as a catalyst precursor in industrial reactions, especially in petroleum and chemical synthesis, including processes for synthetic rubber and plastics.

Applied in laboratories as a reagent for qualitative analysis and in the preparation of other cobalt compounds. Found in some educational demonstrations due to its reversible hydration-dehydration properties.

In agriculture, used in small amounts as a component in fertilizers or animal feed to supplement cobalt essential for vitamin B12 synthesis in ruminants.

Additionally, utilized in the textile and dyeing industry for producing blue or gray colors, and in products requiring environmental color changes.