Thanks for the compliment and thanks for the tip.A woman I know does great work with an Iphone and most of her photos are not level on purpose.She is tempted to buy a drone and needed this info.
When you are static and want to define a special angel gimbal roll adjustment is what you want - as stated before.
When you are moving and filming/taking photos on the go you may want to try the gimbals FOLLOW mode. That gives you a very dynamic perspective. The gimbal will follow the drones movement.