How to create a helper application for Mac App to start it on user login?

Question

In fact, I read the following document:

Applications can contain a helper application as a full application bundle, stored inside the main application bundle in the

Answer 1

Basically you have to take a look at Launch Services which is just a wrapper around launchd, which you can check out by looking at man launchd in the terminal.

or take a look at this question here at SO How do you make your App open at login?