Obstacle aviodance

Does drone deploy fly with obstacle avoidance turned off ? I have noticed when I come back from a mission and then go to DJI 4 app for a second non DD flight, my obstacle avoidance has been turned off. My practice for using DD is to bring up the DJI 4app first, check camera GPS etc, then slide DJI 4 off the screen and bring up DD. Using iPhone 6s.
Thanks.

Same here. In fact my P4P recently crashed into a tree on RTH.