I can't understand why this doesn't work. The error is
Error: Argument 'TodoCtrl' is not a function, got undefined
I guess the issue is simple, but I can't solve it. In general, I want to change the text periodically.
To get your fiddle working I changed the following:
Here is a sample fiddle based on your original fiddle note the following changes based around bypassing jQuery for DOM/model updates:
setInterval
and clearInterval
since modifying the model outside of AngularJS shouldn't be done if easily avoided. If you want to do so be sure and look at $apply.