Does the Friend Radar work when AT&T, Verizon, and festival Wi-Fi are completely dead?

Yes. Bluetooth Low Energy advertising runs peer-to-peer on 2.4 GHz directly between sleeves (or between your sleeve and a friend's phone beacon) with zero cellular or internet dependency.

How do you prevent human bodies in the crowd from making the distance bar jump around?

The firmware smooths proximity readings over 3 seconds, and tapping Pad 3 while raising your forearm above shoulder height clears body-shadowing for clean line-of-sight ranging.

How does the loudness cue work?

Your paired phone's microphone estimates ambient loudness (uncalibrated, not an SPL or OSHA meter) and shifts the 32 columns from green to amber/red when the crowd gets loud.

Use Case #09 · Concerts, Nightlife, Festivals & DJ Booths · All 50 Modes

Dead-Cell Concert & Festival Friend Radar on an 8×32 LED Forearm Sleeve

When every cell tower saturates, find your crew without service: a BLE proximity cue sweeps your 8×32 display from teal to red as you close in, plus a 256-LED Visual Flare — $199.

Peer-to-peer, no signal needed: BLE advertising finds your friends' beacons with zero cellular or Wi-Fi dependency.
Arm-up flare: Press Pad 2 and all 256 LEDs strobe white/orange to signal your group over a packed crowd.
Ready out of the box: Ships as one of the 50 built-in modes; add crew beacons and colors in the Sleeve Studio app.

Preorder Sleeve · $199 Free US Shipping Try in Sleeve Studio →

▶ See the 8×32 Forearm Display in Action

Watch the 8×32 RGB LED matrix and 5 conductive-fabric touch pads running live music, crowd and audio modes on the forearm sleeve. Concept render · simulated 8×32 display · first production run of 500 units.

Why SMS and Find My Friends Fail in a 30,000-Person Crowd

Towers saturate: At big festivals, iMessage and cloud map pins freeze for hours, and pulling out a phone risks theft or a dropped screen.
Signal strength as color: The sleeve listens directly for your crew's beacon and turns RSSI into an unmistakable peripheral bar.
Peer-reviewed textile roots, shipping hardware: The Oct 2026 NUS Nature paper coined “garment GUI” with a lab-only woven pixel fibre (not for sale); our shipping $199 sleeve uses 5 sewn conductive-fabric pads and a removable 8×32 LED pod.

What Each Forearm Pad Does (Pads 1–5)

Pad 1 (Elbow)Single tap — Cycle target crew member beacon (FRIEND 1 / FRIEND 2 / ALL CREW) · LED cue: Scrolls target tag: CREW: MAYA (-62 dBm)

Pad 2 (Upper Mid)Press & hold — Fire Overhead Visual Flare while raising arm above crowd · LED cue: All 256 RGB LEDs strobe high-contrast white/orange at max PWM

Pad 3 (Center)Single tap — Raise-Arm 3-second smoothed proximity scan (a hint, not a compass) · LED cue: 32 columns fill proportionally from cool teal (#0e7470) to red (#ff5a36)

Pad 4 (Lower Mid)Single tap — Toggle the phone-mic loudness cue · LED cue: Right 6 columns shift green → amber/red as the crowd gets loud (uncalibrated)

Pad 5 (Wrist)Double tap — Broadcast 'MEET AT SOUNDSTAGE' preset pulse to paired sleeves · LED cue: Scrolls ACK: SOUNDSTAGE across linked crew sleeves

Customize in 30 seconds: Pick this mode in the Sleeve Studio app, type or speak new words or pad actions, and tap Send over Bluetooth — no code.

Frequently Asked Questions

Does the Friend Radar work when AT&T, Verizon, and festival Wi-Fi are completely dead?: Yes. Bluetooth Low Energy advertising runs peer-to-peer on 2.4 GHz directly between sleeves (or between your sleeve and a friend's phone beacon) with zero cellular or internet dependency.
How do you prevent human bodies in the crowd from making the distance bar jump around?: The firmware smooths proximity readings over 3 seconds, and tapping Pad 3 while raising your forearm above shoulder height clears body-shadowing for clean line-of-sight ranging.
How does the loudness cue work?: Your paired phone's microphone estimates ambient loudness (uncalibrated, not an SPL or OSHA meter) and shifts the 32 columns from green to amber/red when the crowd gets loud.

Run This Mode on Your Forearm — Reserve Batch 01 ($199)

Complete hardware + 50 modes ($199): 8×32 RGB LED matrix (256 pixels), 5 sewn conductive-fabric touch pads, and a 5-second slide-out washable electronics pod.
Sleeve Studio app ships first: Personalize all 50 modes in plain words before your sleeve arrives (small monthly subscription; zero code).
Zero-risk preorder: First run of 500 units (~30 days to production), free US shipping, 100% refund anytime before shipping + 90-day money-back guarantee.

Preorder Sleeve · $199 Free US Shipping Open Sleeve Studio Full Hardware Specs

Watch → Prove → Buy

Not ready to order yet? Take the next step.

See the hardware in motion, read the peer-reviewed textile research behind it, or reserve your spot in the first production run of 500 sleeves.

STEP 1Watch the sleeve in action Five soft touch pads, an 8×32 RGB LED display, Bluetooth, and a removable electronics pod for gentle washing. See the hardware → STEP 2See how the app customizes any mode Pick from 50 pre-built modes or type a new one in plain words. The Sleeve Studio app ships before your hardware. See Sleeve Studio → STEP 3Preorder the Sleeve — $199 First run of 500. ~30 days to production. Free US shipping. Full refund anytime before it ships. Order now →

90-day money-back guarantee, plus a full refund any time before the sleeve ships.

Questions about your setup? Call +1 725-338-4835 or email alex@midnightdev.dev.