The world of wearable gadgets never stops surprising us, and open-source ones make it even more exciting. Pebble, best known for its smartwatches, has introduced Index 01, an open-source smart ring designed as a compact voice-input device for capturing short thoughts, reminders, and notes.
The ring houses a button, a microphone, Bluetooth hardware, local storage, and a long-life silver-oxide battery that lasts for years.
When pressed, it records a brief voice memo that is transferred to the Pebble mobile app once the paired phone is in range. All processing—including speech-to-text and the on-device language model that determines whether to create a note, reminder, or other action—runs locally within the open-source Pebble app.
The ring supports single- and double-click actions for tasks such as controlling music playback or triggering home automation tools. Voice inputs can be routed through MCP actions, which run locally in WASM, or directly forwarded to custom applications via webhook.
On top of that, Pebble plans to expand capabilities with optional double-click-and-hold routing to general voice agents, including integrations with web search or smartwatch-displayed responses.
One of the main selling points in Index 01 is privacy. It records only while the button is pressed, stores audio securely, and requires no internet connection or subscription. Raw audio can be reviewed in the app, and higher-quality cloud speech-to-text is optional.
The design avoids rechargeability to preserve size, durability, and multi-year uptime, with recycling handled by Pebble. So, once the battery reaches the end of its life, it’s simply time to get a new ring. A key advantage is that you never have to take the ring off for the usual, annoying recharging. It stays on your finger at all times, ready to capture any idea the moment it strikes.
The ring itself contains no speaker or haptics to minimize distractions and power usage. Up to five minutes of audio can be stored on-ring before syncing, allowing operation even when the phone is out of range.
The device is made of stainless steel, features an LSR button, and is water-resistant to 1 meter. It ships in eight sizes and three finishes (polished silver, polished gold, and matte black), with worldwide pre-orders open at $75 before rising to $99 when shipments begin in March 2026.
Pebble confirmed full functionality on both iOS and Android, including mobile and smartwatch integration for reviewing captured notes or simple query responses on the watch display.
Development is currently in the DVT phase, with broader alpha testing scheduled for January ahead of mass production.
For more information, visit Pebble’s website.
Image credits: Pebble
