Meet the Phone by Mako. It's a simple, do it yourself phone that teaches you how cellphones work. It comes in a premium, hand-crafted wooden box, with a hand-crafted wooden housing. The phone is powered by the Adafruit Feather FONA, which is an Arduino with a cellular card. The kit also includes a keypad to type in phone numbers, and a 2500mAh battery to last a good long while.
Our mission is to teach people how everyday electronics work by having them build their own version of a device. In the kit, people learn how phones work, how keypads work, and how to code in the Arduino programming language.