SunSpot, a Solar Light Meter for Houseplants

Field notes

SunSpot models a window by combining the phone’s orientation readings with geographic coordinates and solar-position calculations, then presents direct-sun hours and a daylight curve. The homepage’s example uses a south-facing window at 182° with 6.2 daily hours and a 98% plant-match score. It also describes an AR mode for ambient or grow-light measurement, a database covering 85-plus houseplant tolerances, and a seasonal “Sun Shift” feature for deciding when plants need to move.