I'm sure we could live just fine without an iPad, Android phone or television. We can "live" without most "modern" technologies and conveniences, if given sufficient time to adapt. Our species has been there and done that before. The "adapting" part is the tricky part. Until then, technology is actually a sort of liability if a "lights out" scenario ever unfolds. In my estimation, the population concentration in most American cities render them unsustainable by the resources available within them or the local area. Things like food and fuel aren't produced in close proximity to their consumption points anymore, and as such many places are unsustainable without the technology used to keep "just in time" delivery viable. There isn't enough wild game in all of Illinois to feed Chicago for a week, even if you could kill it all, transport it and distribute it before it spoiled. Without the technology used to (for example) ship, preserve, package and inventory goods cities would fall apart within a very short time. Technology does do a wonderful job of leveling the overall playing field as far as competition for increasingly stretched resources. Remove that buffer/crutch/handicap, and then let Darwin throw a pop quiz, and we will likely see what technologies, skills, values and social compacts (and by extension which groups) will hold weight and which will fall by the wayside.