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.
(1) Never draw what you can copy. (2) Never copy what you can trace. (3) Never trace what you can cut out and paste down.