Curious, what revolutionary products would you cite, that existed within 4 years of the underlying technology? I feel like within that time frame, you're looking at "AOL chatrooms" for the internet, and I'm not even sure what the killer app was for smart phones - GPS was around before that.

Computers do admittedly claim the Apollo program pretty early in, so I'll definitely concede that one - just curious if other revolutions have really lived up to that bar. As someone who grew up on modems, I struggle to view the modern world as really having a "killer app" that really couldn't have been done in the 90s