Servers by jDrones

Creatin an android app to control the drone

Hello everyone, I am a student and I want to develop a mobile app for Android in Kotlin language. I have a DJI F450 drone with a Pixhawk 2.4.8 controller, also there is FlySky FS-i6-M2 2.4GHZ Transmitter with receiver and telemetry 433mhz(cp210x). My app should build a route(missions) for the drone, like in QGroundControl or Mission Planner and also should have joysticks for controlling.
The problem is that I cannot imagine the process of how a mobile app connecting with the drone. I know that it could work with the WiFi module or Telemetry, but I can’t imagine how exactly. So my questions are:
Could somebody briefly tell what scheme does the whole process go through? I mean step by step instruction. How to connect the smartphone with the drone through telemetry? How a MAVLink protocol (DroneKit API) sends data? If you know some topics which are better to cover, write pls.
Thanks in advance.

Servers by jDrones