The motivation stems from a cluttered desk filled with various projects and AliExpress orders. The core of the build utilizes a $20 4G modem, the MF800, which offers Wi-Fi, Bluetooth, and a display for under twenty dollars shipped. This cornerstone device runs Android but allows ADB access to enter EDL mode and reflash the unit. The stock software is replaced via the Open Stick project, though driver and device tree development remains the real challenge.

Regarding input, the Clicks Keyboard for iPhone 16 Pro Max offers a premium tactile feel. However, the high cost is exacerbated by the need to modify the hardware. Regarding protocol, it functions as a standard USB keyboard with an additional Apple proprietary endpoint. For output, a Sharp Memory Display board provides high contrast, suiting the "dumb device" use case for messaging exclusively.

A custom adapter PCB was necessary to manage USB host/device mode switching and display power. Because two-sided assembly is expensive, compromises were made to fit components on one side, utilizing the non-component side for solder points. The final device combines the modified 4G modem, adapted keyboard, and custom PCB into a functional texting terminal.

Key Names/Numbers: MF800, Clicks Keyboard, Adafruit SHARPMemory Display, Open Stick, Ch32V203