The unknown causes of threads

Hello. Can somebody explain me why is this happen?
I cant load more than 2 photos, that’s why I will send them later.

Post a screen shot of your storyboard elements showing the ViewController(s) you have added. It’s likely that the default ViewController has not been configured at the “Initial View Controller” (see the attached) and that can happen if you delete and re-add ViewControllers that offer different functionality.