Check out example codes for "Xcode / iOS: How to determine whether code is running in DEBUG / RELEASE build?". It will help you in understanding the concepts better.
Code Example 1
// #if DEBUG will pass in ANY development/ad-hoc build, device or simulator. It's only false for App Store and TestFlight builds. // Example: #if DEBUG print("Not App Store build") #else print("App Store build") #endif
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