Pebble smartwatch creator Eric Migicovsky is venturing into new wearable territory with the Index 01, a minimalist AI-powered ring designed to capture your fleeting thoughts before they disappear. Unlike always-listening AI devices flooding the market, this $75 stainless steel ring takes a distinctly privacy-focused approach to personal note-taking.
The Index 01 operates on a simple principle: press and hold the side button to record your thoughts, and release to stop. No constant listening, no cloud storage concerns. The ring’s name references its intended placement on your index finger, making it easily accessible throughout your day.
How Index 01 Works: Simplicity By Design
Migicovsky’s approach prioritizes solving a single problem exceptionally well. “I think of it as external memory for my brain,” he explained in a recent interview. The ring’s functionality centers around capturing spontaneous ideas that might otherwise be forgotten.
When activated, the Index 01 can record up to five minutes of audio, which syncs to your smartphone via Bluetooth where open-source speech-to-text and AI models process the content locally. This architecture means your personal thoughts remain on your device rather than being uploaded to remote servers—a significant privacy advantage over competing products.
The ring boasts impressive durability specifications. It’s water-resistant to 1 meter, making it suitable for hand washing, dishwashing, and shower use, though swimming remains off-limits. With no need for regular charging, the battery delivers approximately 12-14 hours of active recording time. At typical usage patterns of 10-20 brief recordings daily, Migicovsky estimates around two years of battery life before the ring requires recycling.
Not Just Another Smart Ring
Unlike fitness-focused smart rings, the Index 01 deliberately avoids health tracking features. There are no heart rate sensors, sleep monitoring capabilities, or activity tracking components. Instead, it focuses exclusively on being an always-available thought-capturing tool.
The device supports over 100 languages and includes onboard memory for times when your phone isn’t nearby. Raw audio is preserved alongside transcriptions, ensuring important details aren’t lost due to background noise interference. For existing smartwatch users, recorded thoughts can appear directly on watch screens for immediate verification.
Beyond its primary note-taking function, the ring’s programmable button supports customizable actions. Single or double presses can control music playback, trigger your phone’s camera shutter, or send messages through Beeper (Migicovsky’s universal chat application). The open-source software architecture invites community modifications and extensions.
A Different Business Approach
Core Devices, Migicovsky’s new company behind both the revived Pebble smartwatch and Index 01 ring, represents a deliberate pivot from traditional venture-backed hardware development. After Pebble’s challenging exit to Fitbit (later acquired by Google), Migicovsky is pursuing a sustainability-focused model.
“What I’m doing now is trying an alternative path, which is to start from profitability,” he explains. With just five team members, Core Devices has already successfully launched and sold out the Pebble 2 Duo smartwatch with a black-and-white display. Their upgraded Pebble Time 2, featuring a larger color e-ink screen in a stainless steel body, has secured 25,000 pre-orders.
Market Context and Competitive Landscape
The Index 01 enters an emerging market for voice-note wearables. A notable competitor is Sandbar’s Stream Ring, developed by former Meta employees. While functionally similar, the Stream Ring takes a different approach with its $249 price tag and subscription model offering limited free AI interactions and a $10 monthly premium tier.
Migicovsky’s ring differentiates itself through simplicity, privacy focus, and a no-subscription business model. The $75 pre-order price (increasing to $99 after March 2026) positions it as a more accessible entry point in the smart ring category.
Available in silver, polished gold, and matte black finishes across eight sizes (6-13), the Index 01 works with both iOS and Android devices. It integrates with the Pebble mobile app for basic note functionality but can also connect with calendar systems and productivity tools like Notion.
Real-World Application
After three months of daily use, Migicovsky reports the ring has fundamentally changed how he captures information. The immediacy of having a recording device literally at his fingertips has eliminated the common problem of forgetting ideas before they can be documented.
For professionals who regularly experience inspiration at inconvenient moments—while driving, in the shower, or during exercise—the Index 01 offers a frictionless solution that doesn’t require pulling out a phone or finding a pen. The device’s extended battery life and water resistance ensure it remains available in precisely those situations where traditional note-taking methods fall short.
As wearable technology continues evolving beyond fitness tracking and notifications, the Index 01 represents a focused approach to augmenting human memory through minimal, purpose-built hardware. Whether this specialized approach will find broader market appeal remains to be seen, but it clearly addresses a universal cognitive challenge: capturing fleeting thoughts before they vanish.