How to Test Your iOS App to See if Your Table View Works
Before releasing your iOS app to the world, you need to run it and make sure the table view works. The smallest error can keep your iOS app from working.
To test this part of your app, you need to first stop it in the Simulator (or device) by clicking the Stop button on the Xcode toolbar. Then remove your app from the background by following these steps:
Double-click the Home button Hardware→Home to display the apps running in the background.
Drag the appview up and out of the horizontal list of background apps. If it’s not there, it’s not running in the background.
Run your app.
To test this part of your app again later, you need to first stop it in the Simulator (or device) by clicking the Stop button on the Xcode toolbar. Then remove the app and its user defaults from the device by following these steps:
Press and hold the app icon until it wiggles.
Click the app Delete icon, the circle with the X that appears in the upper-left corner of the icon.
Press the Delete button when asked if you should delete the app and all of its data.
Build and run your app again, with the default destinationPreference again set to nil. This gives you a fresh start.