Please note! Obstacle Avoidance calibrations now occur in-app. If your drone says 'Visual System Calibration Needed', that does not mean the Obstacle Avoidance system is not functioning; it's just recommending a routine manual calibration. You can click 'Forced Open' to use Obstacle Avoidance. This manual calibration being recommended is difficult to do, so we listed tutorials made by 3rd parties above in case you need it. EXO Drones worked extensively to have the calibration be done in-app, so you don't have to do this. Happy flying!