The increasing usage of glyphosate (Glyp) pesticide in agriculture has posed a serious threat to food safety and human health. Herein, a new Ga3+-assisted fluorescent probe BHCM was designed for detecting Glyp residues in foodstuffs, environmental soils, and biological systems. The probe BHCM exhibited dramatically enhanced emission (530 nm) with a large Stokes shift (175 nm) after rapid chelation with Ga3+ (≤6 s) with a low detection limit (22.7 nM). Notably, the BHCM-Ga3+ complex served as a highly specific fluorescent probe for detecting Glyp within 1 min with a low detection limit (19.5 nM). A portable sequential detection platform for Ga3+ and Glyp was fabricated by integrating smartphone software with probe BHCM. The BHCM-Ga3+ complex quantified trace Glyp residues in agricultural products and environmental soils and monitored Glyp fluctuations in living cells, zebrafish, and Arabidopsis thaliana. This approach offers promising pesticide residue tracking in foodstuffs, environmental samples, and biological systems.