[BillinghamJ]

No. I said it "may well be", because a naive implementation using a native language may block while doing IO and be less responsive, unable to do other things while waiting for external stuff to happen.

Perhaps I should have said "may well be more responsive than".

[hollerith]

So, you don't actually know anything about whether native apps block on IO? (I doubt they do on any modern version of Windows, OS X, Linux, Android, iOS or Windows Phone.)

[BillinghamJ]

Depends entirely on the developer. Most APIs support both non-blocking and blocking.