This apnea trainer will help you increase your results in free-diving and breath holding. Includes CO2 and O2 static tables from start. You can make your own table.CAMERA HEART MONITORING ADDED!!!Can measure heart rate with camera, like in Instant Heart Rate app and with Zephyr, Ant+ or Polar Wearlink device via Bluetooth. Approved for professional freediving. Thanks to Zephyr, apnea.cz and Petr Judi for help!!!Bluetooth 4(bluetooth Smart) support is under development!!