apps from the shell

The incantation that I was looking for to start an Android app from within the shell is

am start --user 0 -n net.gsantner.markor/net.gsantner.markor.activity.MainActivity

The problem is identifying the name at the back.

The best source of information seemed to be this Stack Overflow question, but the answers baffled me a bit. Connect my phone over a USB cable to a computer with an Android debugger installed? The Termux Launcher, closest to what I wanted, send to be defunct and couldn't be installed on my device.

The secret sauce was the APK Info app, which I avoided because it wanted to show me ads. But it didn't in the thirty seconds it took to find the correct activityname.

All of these tools have old-fashioned cryptic three letter names, and they all seem to start with a for Android. It's interesting to be at sea in such an environment; I have grown accustomed to knowing my way around.