Degree-Day Phenology Calculator ('shiny' Application) // Provides a 'shiny' application to compute daily and cumulative degree- days from minimum and maximum temperatures using average, single triangle, and single sine methods, with optional upper temperature thresholds. The application maps cumulative thermal accumulation to user-defined developmental stage thresholds and supports exporting tabular and graphical outputs. The degree- day approach follows assumptions described by Higley et al. (1986) doi:10.1093/ee/15.5.999.