I think no, because it uses GC.
JVM has difference GCs, however as I know all of them don’t use reference counting. JS as I know doesn’t use reference counting (however who knows), Kotlin Native doesn’t use reference counting, however iOS integration layers obviously use this behaviour. However all environments have optimisations such as “stack allocations for local objects”, which is looks like reference counting for some cases.
You can use JavaFX for Win/Lin, Android has own UI builders. So answer is no.
From my observations, C++ is much harder than than Kotlin/Rust. Because of compile-time GC in Rust, it is harder than Kotlin from my point of view. So, from my point of view, the answer is “yes”.
This is incorrect question. Multithreaded allocation works faster in JVM than in C++, because it doesn’t require atomic operations (increment requires at about 1-2 processor ticks, atomic increment requires at about 72 for the latest AMD processors). However in C++ you can add more optimizations theoretically. From the another side, JVM better optimises the general code. However in C++ there aren’t array bound verification, so it should faster multiply the matrixes. But for the huge enterprise application, JVM/CLR is the one way to write it and have in workable state for 10 years. So, the right answer - it depends, please do benchmarking first.
From my point of view, JVM is the most easy platform to write once and run everywhere, because of statically-typed nature, because of great backward compatibility, etc. However JVM couldn’t be executed in the Android. So, from my point of view, the answer is yes, however it depends in general case.
Oh I thought it did use JVM, how come it can’t use JVM?
There is OpenJDK on Windows/Linux/Mac. So you can use any modules from it, even JavaFX.
Android doesn’t use OpenJDK, they have separate virtual machines. And the set of features on Android is quite different with set of features on OpenJDK. It means, that you can use Android UI at Android and JavaFX (for example) on Windows Linux. You can write the same code for network and business logic, however UI should be implemented twice.
Therefore: you couldn’t write application on Kotlin JVM, which will be ready for Win/Lin/Mac/Android. However you can share all non-UI code between these platforms if you selected target “JVM” for Kotlin (e.g. UI is the single item which have to be written twice).
Just so I am making sure I am understanding it clearly, JVM is what converts byte/interpreted code into machine code in real time?
Yes, plus “set of API functions”. For example, class File is inside JVM, it isn’t delivered via package manager. Class Process is on JVM 9+ (part of OpenJDK), and it is missed on Android (not sure 100%). Class Intent is on Android VM, however it is missed in the OpenJDK.