Can I make a call with AIR³ without a SIM card?

YES! But you need to have an internet access.

Whatsapp allows you to share your Whatsapp account across multiple devices. Once you have “connected” the AIR³ to your Whatsapp account on your phone, you can use Whatsapp installed on the AIR³ to make calls as long as you have an Internet connection (public wifi, phone hotspot,…).