The Blast sensor performs best when it is within 5 yards of the iOS device and is not blocked by human interference. The antenna may work up to 10-20 yards in certain circumstances, but the progress bar may be delayed and the connection may be lost. The sensor captures actions even when it is out of range of the device. The sensor stores captured actions until the user reconnects to the app. At that time, the stored action data is uploaded and available for viewing.