Check the product name in build settings and make sure everywhere it is Myapp. If that is done,
- Close your project -> go to finder.
- Right click on your .xcodeproject file and click on show package
- Then right click on your project.pbxproj and open it in some text
- Then search for Myapp-temp-caseinsensitive-rename and manually rename
- Save it after changing and then reopen the project.
Make sure you have taken a back up of your project before doing this.