> So your solution to a sandbox app is to buy a Samsung device and use a corporate MDM product to manage that one device?
You implied that no one was making any such thing. They do. An app distributor that wanted to do the same for apps it distributes could do so likewise, but not if Apple stands in their way.
> Google and third parties have been finding bugs in other people’s closed source products for decades. Again just because people can look at code doesn’t mean that people are looking at code.
And if the product was open source, they could also fix the bug, rather than having to rely on the vendor to do it -- which they sometimes don't.
It would also be easier for them to discover the bugs, which would result in more of them being discovered.
> You made the claim that there are less bugs in open source software, without any citations, studies, etc.
Because it's an argument from logic rather than an argument from observation. The claim isn't that some specific number of people have been observed using published source code to discover bugs, only that the number is non-zero -- which doesn't require statistics, only a single counterexample that I can provide myself from personal experience in having done it.
> Android and Darwin are open source but a large part of both iOS and Android are closed source.
Then why propose to compare them as though it would provide some useful information about the effect of open source on finding bugs?