We built Blue, a voice assistant that can use any app on your phone via a tiny USB-C hardware “hand” we call Bud. Here’s how we went from concept to 100 working units in 55 days for YC Demo Day.
3D printed experiments, even the iPhone is 3D printed
The New Way to Use Your Phone with Voice
Blue turns voice into action. Bud enumerates as a standards-based USB HID device and drives iOS’s Accessibility pointer (AssistiveTouch), allowing Blue to tap, swipe, and type across real apps, without requiring APIs or special app integrations. You can say, “Compare these two flights, text the best to John, then buy,” and watch it happen while your hands stay free.
Left: first working prototype, middle: miniaturized, right: production and packaging unit.
The Impossible Deadline.
YC started on July 14 for me, and Alumni Demo Day was on September 7.
I defined “done” as 100 identical, working units that investors and users could plug in and use without any further instruction from us. Claims are easy, but a tray of identical devices is proof.
Sophies Choice(s)
Form factor & pass-through: Bud lives under the phone, featuring a pass-through USB-C port (for charging and CarPlay). The connector height sets the geometry; we locked it early for pocketability and comfort.
Control path: USB HID and iOS Accessibility (pointer + keyboard). No private APIs; universal across apps.
FW/bring-up: Prototyped on Arduino for speed; migrated to a production layout/firmware with our Taiwan partner.
Reliability over features: One PCB, one enclosure, one reliable control path. We paused a battery-Bluetooth concept to avoid adding unknowns for this run.
Ergonomics: Flat bottom (stable on tables), low profile (keeps Bud attached), grippy texture.
The Eight-Week Playbook
We ran parallel workstreams so the line never went cold.
Week 1: Proofs of concept, 3D prints, breadboards, and solder everywhere. Failure by design.
Week 2: A rough unit I could live with for a day.
Week 3: Firmware and iOS bring-up while our Taiwan team started working on the real board.
Week 4: “Pack-and-carry” prototype that survives a backpack.
Week 5: Miniaturization; pass-through height locked hard points.
Week 6: Pilot of four units in Asia; US arrival Aug 20 for fit/feel and simple reliability checks.
Week 7: Green-light the 100 parts, assembly, test; firmware changes are small and safe.
Week 8: Receive, verify, rework, and box 100 for Sep 7. Our partner hand-carried the units to avoid delays.
The Final Orchestration
Evidence over intention: Shipping a mini-run on a clock forces clarity and earns trust.
Scope ruthlessly: One board, one enclosure, one control path beats a bag of features.
Lock hard points early: USB-C pass-through height drove everything else; fixing it early saved days.
Manufacture in parallel: Keep mechanical, firmware, and packaging moving together.
Partners matter: Daily communication with Taiwan, along with decisive morning and evening syncs, ensured that decisions flowed smoothly.
So, What Happened?
We delivered 100 units in 55 days; people could hold them, plug them in, and use them. The first hundred sold/reserved within hours; nearly another hundred joined the second batch in a few days. We’re working toward ~500 units by Nov 2025, prioritizing users who benefit most from hands-free control.
Love it! No more excuses
Congrats. What is the link if I want to order one?