On a broad scale, yes. But it also proves that the efficiency of particular languages depends on the problem at hand. For example, if your problem is searching for a pattern in large strings, a simple Perl program using the builtin regex support will easily beat a C/C++ program that hand-rolls pattern matching, because Perl's regex engine has been optimized for over two decades.

On the topic of mobile devices, I recall the Nokia N900, which ran mostly C and C++ software. Its UI performance was comparable to contemporary smartphones even though it only had 256 MB RAM and a single-core 600 MHz CPU. (Of course, a major part of today's phones' slow UI is all the bullshit and spying that apps are doing in the background.)

If your primary metric for good software is {speed,memory use,energy efficiency} then yes.

Linux and Darwin is written with C. They are the OSs of Android and iOS.

But would be nice to have some mobile apps written with C.

Lots of mobile apps are written in Objective-C, and Objective-C is C. A superset of C to be exact.

Since it's a single hybrid language, it's trivial to remove slower features fro, performance-intensive parts.

See my UIKonf talk https://www.youtube.com/watch?v=kHG_zw7%205SjE&feature=youtu...

Or my book: https://www.amazon.com/gp/product/0321842847/ref=as_li_tl?ie...

Most Android apps use a handful of native code libraries which are bundled inside the apk. It's usual nowadays to only write the UI using Java and use C for the rest.

Linux is just the kernel for Android, the whole userspace is not written in C, and that is what matters in the end for performance and efficiency.