GoKawiilHobbyist turns $20 4G hotspot into a working text messaging gadget
A hardware tinkerer combined a cheap unlocked 4G wireless hotspot, a spare Clicks iPhone keyboard, and an Adafruit Sharp memory display to build a standalone texting device. The project relies on the open-source Openstick effort, which lets Linux replace the Android software running on these budget modems, exposing GPIO and other hardware features needed for the build.
GoKawiil's interpretation of the reporting above, not reported fact.
It shows how inexpensive, mass-produced modem hardware with unlocked bootloaders can be repurposed far beyond its intended use, giving makers a cheap platform for custom communication gadgets. The project also highlights the growing role of open-source firmware projects like Openstick in unlocking commodity IoT hardware for hobbyist innovation.
- A sub-$20 4G hotspot with WiFi, Bluetooth, and battery can be reflashed to run Linux via the Openstick project.
- The build combines a leftover Clicks iPhone keyboard and an Adafruit Sharp display with the modem's exposed GPIO pins.
- Extracting the Android device tree before reflashing was key to understanding and reusing the hardware's capabilities.
Adafruit SHARP Memory Display Breakout — This is the exact display the hacker bolted onto a $20 4G hotspot to turn it into a texting gadget. SHARP memory displays give you crisp, always-on monochrome text with very low power draw, making them perfect for battery-powered handheld builds. Grab one and you're a few GPIO wires away from your own pocket communicator.
See Adafruit SHARP Memory Display Breakout on Amazon → Affiliate link — we may earn a commission on purchases, at no extra cost to you. Product picked by AI based on this article; it is not a tested recommendation.Source: bkovac.github.io, 2026-09-15
Published there as: “Show HN: Hacking a $20 4G wireless hotspot into a texting device”
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