GeoBallistics’ Precision Shooting Wind Meter is a plug-in wind meter for smartphones or tablets, designed for use with the BallisticsARC mobile app. When plugged into the audio jack of the device, it actively measures local wind velocity, with direction measured by the device compass. It is capable of detecting winds from 2 to 125 mph, with an accuracy of +/- 0.5%. The Precision Shooting Wind Meter requires no separate batteries to operate, and comes with a hard case for storage.
geoballistics.com/product/precision-shooting-wind-meter