I think this misses the forest for the trees here. The platforms behavior here is a symptom and not the core problem. I think the following are pretty clearly correct: 1. It's your damn phone and you should be able to install whatever the hell you want on it 2. Having an approved channel for verified app loading is a valuable security tool and greatly reduces the number of malicious apps installed on users devices Gi…
It is an obvious solution, and it's a good first solution. This popup already exists.
A problem in security engineering is that when people are motivated (which is easy to achieve), they will just click through warnings. That is why, for example, browsers are increasingly aggressive about SSL warnings and why modifying some of the Mac security controls make you jump through so many hoops.
The usual take on HN is take the attitude that the developer is absolved of responsibility since they provided a warning to the user. That's not helpful. Users are inundated with stupid warnings and aren't really equipped to deal with a technical message that's in between them and their current desire. They want to click the monkey or install the browser toolbar. The attitude that it's not my problem because I provided a warning they didn't understand doesn't restore the money that was stolen from them by malware.