Show HN: Hacking a $20 4G wireless hotspot into a texting device

2026-09-15 | original

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Why This Matters

A hobbyist repurposed a $20 unlocked 4G hotspot into a standalone texting device by flashing Linux onto it via the openstick project and pairing it with a Clicks iPhone keyboard and a SHARP memory display. It's a striking illustration of how cheap, capable cellular hardware has become, and how open firmware tooling can turn commodity gadgets into general-purpose Linux computers with LTE built in.

Key Takeaways

Sub-$20 hotspots ship with a 4G modem, WiFi, Bluetooth, display and battery — and are fully unlocked.
The openstick project plus adb/EDL access makes flashing Linux onto these devices straightforward, though not painless.
Combining off-the-shelf parts (Clicks keyboard, SHARP memory display) yields a DIY alternative to purpose-built texting hardware.

Worth a Look

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.

Converting a $20 4G wireless hotspot into a texting device

Also known as: we have the Clicks Communicator at home.

The thing

The motivation.

I don’t organize my things well. I try to, but quite often end up with a bunch of stuff on my desk. From various aliexpress orders and projects I’m working on, all the way to gifts and stuff I didn’t have time to find a place for.

That is exactly how this project came to be. At one point in time I had, lying on my desk:

Various, hopefully openstick compatible, models - namely the: MF800 - one I ended up using UZ801 - OK size, but no battery or sufficienet visible GPIO USB drive form factor one I ditched because of other issues

The Clicks Keyboard for iPhone 16 Pro Max (gift from my cousin - too bad I don’t have an appropriate iPhone 🥲)

The Adafruit SHARP Memory Display board

And of course, my caveman brain combined the 3.

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Explore topics: 4g hotspot clicks keyboard openstick mf800 sharp memory display