When developing in iPhone in Xcode and you change an image it might not be updated when you run it on your device or simulator as it’s still use the old image. The error can be caused by different factor but can be solved by doing some or all of these steps.
- Uninstall the app on your device before deploying it again.
- Close and reopen the simulator.
- Clean the project, in the menu Product -> Clean. (Shift + Cmd + K).
Cleaning the project will solve most issue relating resources not updating correctly.