Tower Rush

Tower Rush is an easy‑to‑use tool that calculates when a primary rainbow can appear from a chosen lookout. It uses the NOAA solar equations to determine the sun’s height and direction minute by minute for each day of the week. The app lets you enter the latitude, longitude, time zone, bearing and view width of each lookout. It then marks the time windows when the rainbow’s top (about 42°) falls within that view, displaying the results on a weekly clock‑style chart. You can tap any window to see a scaled drawing of the rainbow on the horizon, with a secondary bow at about 51°. The chart also shows a reminder that can alert you 40 minutes before a planned shoot. After each outing you can log the result, and the app draws a chart comparing the sun’s height with the 42° line, highlighting successful shoots and missed opportunities for each lookout. All content is included in the app and works completely offline. With Tower Rush, your favorites, notes, progress, and personal data are stored only on your device, with no registration, accounts, or cloud synchronization required.