What are "Connected Apps"?

[kilgetty]

On checking out my new Nexus 7 I tapped "Google Settings">"Connected Apps" and found three entries, "Mobile Nations", "My Bitdefender" and "Safe in Cloud". As I don't know where they came from or what they are for, I selected disconnect, but each one came back with the message that I am unable to do this.
I would be interested to know why they are there, do I need them, and how to get rid of them if I don't.

 

[patruns]

All 3 of those are apps you (or someone) has installed.

 

[RobAl33]

I assume you have the android central app, as mobile nations is parent of ANdroid central hence is the connection.

I would assume these others are associated with other apps you have installed but they aren't being clear.