App Title

Open file mdelicious_source/lib/constants/strings.dart change Mdelicious to Your App Name

Android App Name

Open file mdelicious_source/android/app/src/main/res/values/strings.xml change your app name

iOS App Name

Click to file mdelicious_source/ios/Runner.xcworkspace in folder ios to open the project on XCode then update your app name like the screenshot below.