A:Answer 1.) There is a SD card slot, but no USB. Printing from the card is supported.
2.) Apple AirPrint and whatever Android phones use is supported. I print from my iPhone 6s plus with no issues.
3.) I have not bought replacement ink yet, but from what I've seen in pricing, it is competitive with other brands and similar models. Combo pack (black and color together) at Best Buy is around $37, maybe cheaper if its on sale.