configuration subscription

I would like to offer you an idea for a subscription to iPhone / iPad resources. In a nutshell. The devices are available with maximum memory capacity and LTE module (for iPad). But from the box are available in the minimum configuration. For example - 32gb memory, 2 processor cores, 8 megapixel camera and no LTE for iPad. If the user needs more space or a higher resolution of the camera, he pays through iCloud for this option for a month and uses it as long as he needs it. Likewise - LTE for iPad.