The current cost for a single pair of adjustable glasses is approximately $19. With increased mass production and emerging technology enabling delivery by anyone with minimal training, the cost per unit will significantly decrease.
So premade glasses and the smartphone app would be cheaper currently, but if the technology becomes popular, this may be cheaper.
"I've seen the forgeries I've sent out." -- John F. Haugh II (jfh@rpp386.Dallas.TX.US), about forging net news articles