How can I deduce/identify an app from a notification icon? I'm concerned about an app on my child's phone. I saw an app icon in the notification area that looked strange (Andy Android head, slightly tilted as its icon).

How can I find out what app it is from just having seen that icon in the notification bar?
You need to investigate this on your own. There's a generic way to do this:
There are at least 4 possibilities:

If the phone has Android 4.1 or later you can long press the notification and see the App info:


Look that App icon up in the list of installed  apps on the phone
Settings-&gt;Apps-&gt;installed apps

Just click it and see what app starts

Go to the Play store and look through the installed apps on [phone] list
To access this you need to be logged in with your kid's Google account. On the phone itself this is automatically the case, on the PC you need to enter username/password.