Well, I'm not sure about the pricing, but according to this page (https://realm.io/products/realm-mobile-platform/ https://realm.io/products/realm-mobile-platfo

Well, I'm not sure about the pricing, but according to this page (https://realm.io/products/realm-mobile-platform/ https://realm.io/products/realm-mobile-platform/) you can host the mobile platform on-premises.