Cyanobacteria are photosynthetic organisms that flourish with nominal light, carbon dioxide, and water. They attain their nitrogen necessity through nitrogen fixation, which makes them beneficial for agronomical applications as biofertilizers and produce various bioactive compounds or secondary metabolites which improve crop growth, provide protection against pathogens, and boost soil nutrient status. These compounds encompass peptides, polyketides, amides, terpenoids, steroids, and alkaloids, with peptides comprising 61.5% of the total. Mostly exhibit bioactivities such as cytotoxicity, enzyme inhibition, microbicidal, antiprotozoal, and anti-inflammatory properties. The structural diversity and composition differences among cyanobacterial populations propose their role as signaling and regulatory molecules. Nostoc muscorum, a free-living cyanobacterium, inhabits in terrestrial and freshwater environments and biosynthesizes substances with notable bioactivities with plausible biotechnological applications, comprising mycosporine-like amino acids, carotenoids, sugars, and principal fatty acids. Cultivation of Nostoc requires optimal growth conditions like light, temperature, and nutrients to encourage the formation of hormogonia (motile filaments) and colony development. Due to its exceptional properties and desirable compounds, Nostoc biomass has various applications in biofertilizers, bioremediation, biofuels, nutraceuticals, and pharmaceuticals. This chapter focuses on the emerging utilizations, trends, and prospects of cyanobacteria-derived secondary metabolites and Nostoc biomass, emphasizing their role in upgrading environmental sustainability and human health.