Using printf in native iOS plugin?

Hi there,
looked through thee forum but did not find an answer to my question (maybe bcause it is too stupid).
But I really got stuck debugging a plugin written Objective-C.
To bette understand what is rally going on within the plugin I want to add some old-fashioned print statements.
So I instrumented my code with a few printf(“hi I am here…”) but they never show up in the console log. I am deploying the App on my iPhone and whatch what is going on during runtime…

What am I overlooking … ?

Thank you for your support.
Markus.