Chatter 2.0 uses LoRa (Long Range) radio communication, which provides impressive range for a small device:
Open area (line of sight): Up to 1–2 km depending on conditions.
Urban environment (buildings, walls): Typically 200–500 meters.
Indoors (same building): Works well across most typical buildings.
Range depends on several factors including obstacles, interference from other radio devices, antenna orientation, and weather conditions. For best results, keep the devices upright and avoid placing them near large metal objects.