Yes, it’s all in how you set it up. This app uses hub modes to arm/disarm it’s monitoring (with an optional delay and you’ll see why it’s needed below).
If you’re using the Lock User Management app, configure it to change the mode to “away” mode when the lock is locked (you can select how it’s locked, using pinpad or manually, so you can set “away” mode when locked via pinpad and “home” mode when locked manually). Also set the app to change your mode to “Home” when it’s unlocked via the pinpad.
Set the Intruder alert app to arm the monitoring when it’s in “away” mode. Now it anything opens or there is motion (however you configure it) it’ll set off the alarm and notify you.
When the lock is unlocked the user management app will change the mode to “Home”. Now the Intruder app will no longer alarm when a door/window is opened.
Remember I mentioned setting a delay in the Intruder app, that’s important here since when you unlock smartthings can take a few seconds for the mode to change, if you open the door immediately it may set off the alarm, this is where the delay comes in handy. You can delay setting off the alarm and if the mode hasn’t changed (actual intruder) the alarm goes off.
It’s quite flexible depending on how you want to configure/use it.