My drone is mavic 2 pro. I has use Litchi before.But i don,t know how to install the app in the smart remote.
The easiest way is: Go to the Litchi website and read their instructions.
Your Mavic 2 Pro is by a wide margin the most capable DJI drone compatible with Litchi. Once you get Litchi up and running you will agree that no other drone is better suited to Litchi than the Mavic 2 Pro. I like the M2P so much that I acquired two of them.