Concept render4G watch
Senior watch with SOS
A cellular watch with one large SOS button, fall alerts, location and two-way voice. It works away from home with no phone to pair.
Products · Elder care & companions
A device an older adult can use without help, that keeps working when Wi-Fi drops or a cloud service goes away.
We design and build 4G senior watches with SOS and fall alerts, check-in speakers and desk companions. Provisioned in the box, loud and clear, with core features that run offline and data that goes only to your cloud. We build for adults, older adults and teens 13 and up.
Concept renderForm factors
What an elder care or companion device can look like
These devices succeed when they fit a daily routine with no setup and no phone. Three common forms, and three more we can build.
Concept render
Concept renderCheck-in speaker
Check-in and reminder speaker
Daily check-ins, medication and appointment reminders, and a one-press call to family. One big button, loud clear speech, nothing to set up.
Concept renderDesk companion
Desk companion with a display
A small screen, far-field mics and a speaker for a conversational companion, coach or assistant. Wake word runs on the device.
Pendant
SOS pendant or clip
A single-button alert worn on a cord or belt for people who will not wear a watch. Bluetooth LE to a home hub, or LTE-M on its own.
Reminder dock
Medication reminder dock
A dock with lights, a speaker and a lid sensor that logs when a dose was taken and tells a caregiver when one was missed.
Bedside
Bedside check-in unit
A night light, a call button and a motion sensor that report a normal morning, or no movement by a set time, to a caregiver.
Who it is for
Built for the user, bought by the people around them
The person wearing the watch is often not the person who buys it or sets it up. We design for both.
Older adults
People living on their own
Devices they can use with no help, no app and no passwords. Large controls, clear speech and a button that always reaches someone.
Caregivers
Family and paid caregivers
A caregiver app for alerts, check-in status, reminders and settings, so the older adult never has to change anything on the device.
Senior living
Communities and home-care operators
Fleets provisioned in bulk, alerts routed to staff or the monitoring service you contract, and update control at fleet level.
Ages 13+
Adults and teens for companions
Desk and home companions for adults and teens aged 13 and up, with age gating and the safety features your counsel requires.
Who we do not build for. We do not build products for children under 13, and we do not build children's products of any kind. Teen-facing companions need age-appropriate design and safety features, which we scope with your counsel at Gate 0.
System
From the SOS button to your care service
An elder care device is five systems that must agree on what happens when something goes wrong. We build the first four and test against the fifth.
- 01
Device
Enclosure, buttons, mics, speaker, display, IMU, GNSS and battery, designed for hands and ears that are not young.
- 02
Firmware
SOS and fall-alert state machine, offline features, wake word, reminders, signed OTA and a defined behavior for every failure.
- 03
Connectivity
LTE-M or Cat-1bis with your SIM, Wi-Fi and BLE. Provisioned in the box, so the user never joins a network.
- 04
App & backend
Optional. Caregiver app, alert routing, device management and storage, deployed in your cloud account.
- 05 · YOURS
Your service
Your monitoring service, AI companion, care program or subscription. We test against your endpoint.
Reference architecture
Inside a senior watch and a desk companion
The watch is a cellular tracker with a voice path and a fall-alert trigger. The desk companion is a far-field voice device. The choices inside each block decide runtime, cost and what still works offline.
A 4G senior watch
| Block | For example | Why it matters |
|---|---|---|
| Cellular | Cat-1bis such as the u-blox LEXI-R10 family, or LTE-M such as the Nordic nRF9151 with integrated GNSS | Two-way voice needs a module and firmware whose VoLTE is approved on your carrier. We confirm this at Gate 0. |
| Location | GNSS on the module or a separate receiver such as u-blox M10; Wi-Fi and cell-ID as indoor fallbacks | GNSS rarely works indoors, which is where most alerts happen |
| Motion | 6-axis IMU such as Bosch BMI270 or ST LSM6DSV, with on-chip motion detection | Triggers a fall alert prompt. The IMU wakes the MCU so standby stays low. |
| Button and haptics | One large SOS button with a long-press threshold, a vibration motor and a status LED | Must be easy to press on purpose and hard to press by accident |
| Audio | MEMS mic and a speaker sized for speech, with a sealed acoustic path | The wearer may be on the floor with the watch away from their ear |
| Power | Li-Po cell, PMIC and fuel gauge; magnetic or drop-in dock charging | Runtime depends on GNSS and voice use. We measure it on the Gate 1 prototype. |
A desk companion
| Block | For example | Why it matters |
|---|---|---|
| Application SoC | Espressif ESP32-S3, or ESP32-P4 paired with an ESP32-C6 for Wi-Fi 6 and BLE; a Linux SoC such as NXP i.MX 93 if more must run locally | Decides which features still work with no network at all |
| Audio input | 2–4 MEMS mics with acoustic echo cancellation, for example an XMOS XVF3800 voice processor or AEC on the SoC | Older adults often speak softly and from across the room, with a TV on |
| Audio output | Class-D amplifier and a speaker in a tuned enclosure, sized for clear speech | Speech clarity matters more than music quality for this group |
| Display and controls | Small LCD with large type, physical buttons, and a mute switch that cuts mic power | People must see when it is listening and be able to stop it by hand |
| Connectivity | Wi-Fi and BLE; optional LTE Cat-1bis for homes without broadband | An LTE variant adds the cellular certification path |
| Cloud | Your LLM and voice backend, reached through an endpoint set in signed configuration | The device must keep working if that backend changes or goes away |
Part names are examples only. Final selection happens at Gate 0 against your runtime, size, cost, carrier and module-origin requirements.
Design for older users
Nothing to learn, nothing to set up
Many older adults have arthritis, hearing loss or low vision, and no interest in another app. Most of the design work goes into removing steps.
01 · Controls
Large, few and physical
One SOS button, a few large keys, high-contrast type and a screen that never needs a swipe to reach an alert.
02 · Audio
Loud and clear speech
Speaker and enclosure tuned for intelligibility, a wide volume range for users with hearing loss, and prompts that repeat.
03 · No setup
Provisioned in the box
SIM active, contacts and settings loaded before shipping. The user takes it out, charges it and it works.
04 · Caregiver app
Changes happen remotely
Contacts, reminders, check-in times and alert routing are set by a caregiver, with the user told on the device when something changes.
05 · Charging
Works with arthritis
A magnetic or drop-in dock instead of a small plug, a charge level shown in words, and a reminder to charge before the battery runs low.
06 · Offline
Core features need no network
SOS to a stored contact over cellular, reminders, clock, alarms and the wake word all run if Wi-Fi drops or your backend is down.
Designed for the worst day
When Wi-Fi drops or a cloud service goes away
In late 2024 a well-known companion robot lost almost all of its features when its maker closed, because every conversation depended on the maker's servers. Families who had built routines around it were left with a device that could not talk. We design so your users do not face that.
- Local fallback. SOS, reminders, clock, alarms, saved contacts and a fixed set of voice commands work with no network. The device says clearly when it is offline.
- Swappable backend. The cloud address, model provider and credentials live in signed configuration. You can change provider or host without a hardware change.
- End-of-service image. We build and test firmware that switches devices to local-only mode and exports user data. You keep the image and the signing keys.
- Documented protocol. The device-to-cloud protocol is documented and the firmware source is yours, so a successor could run a compatible server.
- No remote kill. The device does not need a server to boot or to keep its local features. An expired account loses cloud features only.
Fall alerts and SOS
Alerts that reach a person, with honest limits
An SOS button and a fall alert send a message and open a voice call to family or to a monitoring service you contract. We do not claim medical-grade fall detection, and we do not claim a connection to emergency services unless your carrier setup supports it and you have confirmed it.
As of October 2026, FDA's general wellness guidance does not address fall alerts directly. Intended-use wording is set with your regulatory counsel.
- SOS button. Long press to send, with a vibration and a spoken confirmation, so a bump does not raise an alarm and a real press is never in doubt.
- Fall alert. The IMU flags a likely fall. The watch asks "Are you OK?" with a countdown, and sends the alert if the wearer does not cancel it.
- Location with the alert. GNSS outdoors, Wi-Fi and cell-ID indoors, and a BLE beacon to tell "at home" from "out".
- Escalation. Contacts are tried in order until someone acknowledges, with the rules set in the caregiver app.
- Measured in the pilot. False alarms and missed falls both happen. We log both in the pilot so your copy and your support team can be accurate.
Certification path
What an elder care or companion device must pass in the US
A Wi-Fi speaker on a listed adapter has a short path. A cellular watch worn on the wrist has one of the longest. We map yours at Gate 0 and file in your company's name.
| Requirement | When it applies | How we handle it |
|---|---|---|
| FCC Part 15 Subparts B and C | Every device: unintentional emissions, plus Wi-Fi and Bluetooth transmitters | Pre-certified modules where they fit. The finished device still needs Part 15B testing. |
| FCC Parts 22, 24 and 27, PTCRB, carrier | The 4G watch and any LTE variant | Same path as our LTE trackers. Voice adds carrier VoLTE testing. Planned at Gate 0 with lab quotes. |
| RF exposure and SAR (47 CFR §2.1093) | Devices used within 20 cm of the body, such as a cellular watch or pendant | A body-worn cellular device usually needs SAR testing. A desk unit used at 20 cm or more is assessed as a mobile device instead. |
| 911 calls (47 CFR §9.10) | Only if the watch can dial 911 | The rule applies to the carrier that provides interconnected voice. We confirm 911 behavior with your carrier before any copy mentions it. |
| UN38.3 + 49 CFR §173.185 | Any lithium cell shipped with or in the device | Test summary from the cell supplier, planned at Gate 2. |
| Listed power adapter + DOE Level VI | Plug-in devices such as speakers, desk units and docks | We specify a listed external adapter that meets the federal Level VI efficiency standard, so the device has no mains stage of its own. |
| California SB 243 | Companion chatbots used in California, in effect since January 1, 2026 | Duties fall on the operator, usually you. The device must support a spoken and visible AI notice and a tested crisis-referral audio path. |
| COPPA (16 CFR Part 312) | Online services directed to children under 13 | Why we do not build products for children under 13. Voice recordings and street-level location of a child are personal information under the rule. |
Rules as of October 2026. This is engineering guidance, not legal advice. Primary sources: 47 CFR Part 15, 47 CFR §2.1093, 47 CFR §9.10, 49 CFR §173.185, 10 CFR §430.32, California SB 243, 16 CFR Part 312. Lab and certification fees are paid by you; we manage the process. How we plan FCC work.
Small batches
How a 10–1,000 units run works for an elder care device
These products are proven in daily use. Put real units with real older adults early, with one community or caregiver group, then tool up.
- Gate 1, works-like (3–5 units, 3–6 weeks). Module and SoC dev boards on a custom carrier. SOS, alerts and offline features working against your endpoint.
- Gate 2, EVT (10–30 units, 6–10 weeks). Custom board, first enclosure with acoustic tuning, dock charging, measured runtime and end-of-service image tested.
- Gate 3, pilot (10–1,000 units, 8–16 weeks). A pilot with one senior-living community or caregiver group while FCC, PTCRB and carrier testing run.
Every unit off the line goes through a production test we write with you:
- Speaker-to-mic loopback in an acoustic box for response, distortion and echo-cancellation reference
- SOS button force and travel, haptics, LEDs, display and mute-switch checks
- LTE attach and a test call on your SIM; Wi-Fi and BLE checks
- GNSS fix against a simulator or reference signal, and an IMU self-test
- Charge, dock contact and battery capacity sampled per lot; credentials written to a manifest you keep
Privacy in the home
Health, location and voice data stay with you
These devices hear family life, know where someone is and when they fell. Only your systems should ever see that.
- No Duobay server and no China-hosted service in the data path. Recordings, alerts, location and health data go to your backend or a US cloud region you choose.
- Caregiver access is set with the user's consent, and the device tells the user when someone else can see alerts, location or conversations.
- Wake-word detection runs on the device, so audio leaves only after the wake word or a button press.
- A mute switch that cuts power to the mics, and a listening light wired to the same rail, so firmware cannot override either.
- You hold the signing keys and device credentials, and receive firmware source and an SBOM at every gate, including every on-device model and its license.
Start from proven work
Reference design and reading
Concept renderLTE and GNSS tracker
The cellular, location and power base a 4G senior watch builds on: LTE-M or Cat-1bis, GNSS, and firmware that reports to your server.
View design →Further reading
AI companion compliance for teens and older adults
COPPA, California SB 243, recording consent and RF exposure, and what each means for the hardware.
Elder care and companion devices: common questions
Is the fall alert a medical device?
We design it as an alert to family or a monitoring service, and we do not describe it as medical-grade fall detection. Whether your product needs FDA review depends on your intended-use claims. FDA's general wellness guidance (January 2026) does not address fall alerts directly, so settle the wording with your regulatory counsel before marketing copy is written.
Can the SOS button call 911?
Only if your carrier and voice setup support it, and we confirm that before any copy mentions it. FCC 911 rules (47 CFR §9.10) apply to the carrier that provides interconnected voice service. By default the SOS button calls and alerts the contacts or monitoring service you set up.
Do you build devices for children?
No. We build for adults, older adults, and teens aged 13 and up for companion products. We do not take products directed to children under 13. The amended COPPA rule had a compliance date of April 22, 2026, and treats a child's voice recordings and location as personal information.
Does California SB 243 apply to a check-in speaker?
It depends on what the device does. SB 243 covers companion chatbots that sustain a relationship across interactions. A conversational companion likely falls inside it. Whether a reminder-only speaker does depends on its features, so your counsel should confirm.
What happens to the devices if our AI provider or company shuts down?
They keep working in a reduced local mode. We design a local fallback, a cloud endpoint set by configuration, and an end-of-service firmware image that you build and keep on file with your own signing keys.
Do older users need Wi-Fi or a smartphone?
No. The watch has its own cellular connection, and speakers and desk units can have an LTE Cat-1bis variant for homes without broadband. A caregiver uses the phone app. The older adult does not need one.
Next step. Tell us who will use the device, who will set it up, who receives the alerts and what it must do with no network. A Duobay engineer replies within 2 business days.