The Space weather-based position error maps for TEC-On-Line (SpoT-On) project will use GPS=GNSS based TEC data, integrated into the Global Assimilation of Ionospheric Measurements (GAIM) operational system at the Utah State University Space Weather Center to product improved TEC position correction maps. These will be publicly and globally accessible. A result is that agencies, industry and consumers will enjoy much higher accuracy position information than is currently available from single frequency GPS/GNSS receivers. In Phase I-III, we will demonstrate a prototype capability, constructs a development and deployment plan, develop the operational capability, and deploy this system commercially. Validation and design tasks include initially using the existing GAIM Gauss-Markov(GM) model to produce global TEC correction maps and correction coefficients that can replace Klobuchar correction coefficients. Development and verification tasks will then extend the system to use the GAIM Full Physics (FP) model in a operational capability demonstration for even more accurate, reliable correction coefficients for TEC, including at high latitudes,. The deployment of the system will consist of using both smart phone apps and an industrial version of the system to serve updated coefficients to the GPS system as a whole through telecommunications and agency providers.