Used as a source of tungsten in catalysts for petroleum refining and chemical synthesis, where it promotes selective oxidation reactions. Employed in electroplating baths to deposit wear-resistant tungsten coatings on metals, often in combination with nickel or cobalt. Applied in corrosion inhibitors for industrial water systems, forming protective films on metal surfaces. Utilized in research for synthesizing tungsten-based nanomaterials and pigments. Also serves in analytical chemistry as a reagent for detecting phosphates and silicates.