NFC, seems to me like a patch sized antenna (looks to the other half of 808) it's not thicker than 1 or 2mm maximum.
Despite the undeniable coolness of the Sollar OH I may drop it in favor of an attractive keyboard other half. At that point I don't see myself swap my keyboard for the Sollar OH unless I am somewhere in the dessert.
Can this I2C connector be passed through to another attached 2nd other third?
What about stackable other halves?