Let me give you a complete answer to your question. Changing the status bar text colour is very easy but its a little confusing in iOS 7 specially for newbies.
If you are trying to change the colour from black to white in StoryBoard by selecting the view controller and going to Simulated Metrics on the right side, it won't work and i don't know why. It should work by changing like this but any how.
Secondly, you won't find UIViewControllerBasedStatusBarAppearance property in your plist but by default its not there. You have to add it by yourself by clicking on the + button and then set it to NO.

Lastly, you have to go to your AppDelegate.m file and add the following in didFinishLaunchingWithOptions method, add the following line:
[[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleLightContent];
This will change the colour to white for all your view controllers. Hope this helps!