Litchi is THE app to get once you master the basics of your drone..
The options and possibilities are limitless. For example you can pre-plan your mission from your computer at home for say 20 mins of fly time and 100s of waypoints way further than the connection between your remote and the drone .. so essentially you can loose conection to the drone and still go on its mission and then its can do all sort of things during the mission and it is 100% guaranteed that it will return home whatever happens.. like running out of battery or end of mission etc ..
Only thing to worry about is height of drone during mission (like a tall building or a tree in its flight path) or the return to home path which is a straight line might hit something tall if battery runs out during the mission. Otherwise you program the mission to have the last waypoints towards the home point.
The smoothness of the videos you can take using litchi can not be equaled by manual flying... it is cinema smooth perfect!
At any point if you have connection to the drone you can flip to sport mode and back to gain control of the mavic and end the mission.
for example this video is about 13km distance in total and lost connection to the drone allmost immediately due to the trees:
And then this video demonstrates how smooth the video action is:
Enjoy!