How to make sure drone is connected through specific QGC app and not from any other QGC or other ground control app

How to make sure drone is connected through specific QGC app and not from any other QGC or other ground control app.
I will be customizing QGC and will install on client’s tablet, But I don’t want my drone to be connected by any other app.

You could set a specific system ID in the QGC settings and distinguish the ground station based on that on the PX4 side

I assume what you actually would want is some sort of proper access control which would be a bit more involved to get right. You could e.g. do that somewhere on the network layer where all the mavlink traffic has to go through and implement something like a NAT, so a firewall which only accepts commands from one source.