Qalvin enables you to calibrate your powermeter’s slope by hanging weights from the bike’s cranks. This video explains what weights to use and how to set up the bike, and goes through the calibration process end-to-end.
Qalvin is Quarq’s application for iPod Touch, iPhone and iPad that enables calibration and advanced diagnostics of CinQo powermeters. It is a free application and available from Apple’s App Store.
You need the Wahoo Key (formerly called the Fisica Fitness Sensor Key) to operate Qalvin. This is an ANT+ transceiver that plugs into your iPod Touch, iPhone or iPad and must be purchased separately.