Models that support Smart Keyboard and Smart Keyboard Folio
The following models support Smart Keyboard:
iPad Pro 12.9-inch (1st and 2nd generation)
iPad Pro 10.5-inch
iPad Pro 9.7-inch
iPad Air (3rd generation)
iPad (7th generation)
The following models support Smart Keyboard Folio:
iPad Pro 12.9-inch (3rd generation and later)
iPad Pro 11-inch