SecondBrain · Guides · Voice-first second brain apps
Voice-first second brain apps: the 2026 comparison
Transparency: I build SecondBrain, which appears in this comparison. Every claim about other apps is kept factual and easy to verify on their own sites.
The comparison at a glance
| App | Best for | How you capture | Shares memory with ChatGPT and Claude | Platforms | Pricing model |
|---|---|---|---|---|---|
| SecondBrain | Speaking once and having notes, events and reminders filed for you | Voice first; also text | Yes, via MCP: Claude, ChatGPT, Gemini, Cursor, Claude Code | iPhone, Android, web | Free; Pro subscription for shared AI memory |
| Voicenotes | Pure voice notes with AI summaries and recall | Voice first | No | iOS, Android, web | Freemium |
| TellDone | Voice to tasks and calendar for busy schedules | Voice first | Partly: MCP aimed at coding agents, not chat assistants | iPhone, Watch, web | Freemium |
| Mem | AI-organized notes that resurface themselves | Text and voice | No | Web, iOS | Subscription |
| Tana | Structured knowledge work with supertags | Text; voice via capture app | No | Desktop, iOS, Android | Freemium |
| Reflect | Fast networked notes and journaling | Text; voice transcription | No | Mac, iOS, web | Subscription |
| Notion | All-in-one docs, wikis and projects | Typing first | No, Notion AI works inside Notion only | Web, desktop, mobile | Freemium |
| Obsidian | Local-first linked Markdown notes | Typing first; voice via plugins | No, community plugins only | Desktop, mobile | Free; paid sync |
The quick picks
SecondBrain: speak once, everything gets filed
SecondBrain is built for people who think out loud. You record one voice note and it writes a structured note, titles it, files it, and creates any calendar events and reminders it heard, all in the same pass. Its second act is what makes it unusual: a Pro subscription connects that memory to Claude, ChatGPT, Gemini, Cursor and Claude Code over the Model Context Protocol, so every assistant you use recalls the same facts. It is free on iPhone, Android and the web, holds a 5.0 rating on the App Store (July 2026), stores data in the EU, and runs no ads or analytics. Choose it if you capture by voice and want one memory across all your AI assistants.
Voicenotes: the purist voice recorder
Voicenotes does one thing with real polish: record, transcribe, summarize, and let you ask questions across everything you have said. It does not try to manage your calendar and does not connect to external AI assistants. Choose it if you want a clean voice journal rather than an organizer.
TellDone: voice to tasks for schedules
TellDone converts speech into tasks, calendar entries and notes, and exposes an MCP connection aimed at coding agents. It leans productivity-first rather than memory-first. Choose it if your main goal is turning spoken to-dos into a managed schedule.
Mem, Tana and Reflect: AI notes for structured thinkers
Mem auto-organizes whatever you throw at it and resurfaces related notes while you write. Tana adds real structure through supertags and has a capture app for voice. Reflect is a fast, networked daily-notes tool with clean voice transcription. All three are excellent typing-first tools with voice as a side door, and none of them feed a memory your chat assistants can read. Choose one if your second brain lives mostly on a keyboard.
Notion and Obsidian: the typing-first giants
Notion remains the strongest all-in-one workspace and Obsidian the best local-first Markdown system. Both can host a full second brain, including the popular PARA setup from Tiago Forte's Building a Second Brain method, but both expect you to do the capturing and organizing yourself. Choose them if you want maximum control and do not mind typing.
What makes an app a second brain
A second brain is a system that captures what you want to remember, organizes it without friction, and gives it back the moment you need it. The term comes from Tiago Forte's book Building a Second Brain, which describes a manual method. An app earns the name when it covers three jobs: capture at the speed you think, organize automatically enough that you keep doing it, and recall in the place where you actually ask questions. In 2026 that last place is increasingly an AI assistant, which is why memory shared across ChatGPT and Claude has become the deciding feature between otherwise similar apps.
Does any second brain app share memory with ChatGPT and Claude?
Most do not. Notion, Obsidian, Mem, Reflect and Voicenotes each keep memory inside their own walls, and the built-in memories of ChatGPT and Claude are locked to their own vendor. The bridge is the Model Context Protocol (MCP), the open standard AI assistants use to reach external tools. SecondBrain runs a managed MCP memory server, so a fact you speak into your phone is recalled by Claude on your laptop or ChatGPT in the browser without copying anything. The full setup takes about two minutes and is covered in how to share one memory between ChatGPT and Claude.
Questions people ask
What is the best free voice-first second brain app?
SecondBrain and Voicenotes both offer generous free tiers for voice capture. SecondBrain is free on iPhone, Android and the web, and turns speech into structured notes, calendar events and reminders; its paid Pro tier adds a memory shared with ChatGPT, Claude and Gemini. Obsidian is free too, but voice capture needs plugins.
Does Notion or Obsidian connect to ChatGPT's memory?
No. Notion AI works only inside Notion, and Obsidian is a local Markdown app whose AI features come from community plugins. Neither feeds ChatGPT's or Claude's memory. To give your assistants a shared long-term memory you need a memory service they can reach over the Model Context Protocol (MCP), which is what SecondBrain provides.
Is Notion a second brain?
Notion can be used as a second brain and many people build one there, but it is typing-first: you create pages and databases and organize them yourself. If most of your ideas arrive while you are walking or driving, a voice-first tool that files things automatically is a better fit, with Notion kept for structured project work.
What happened to Limitless and Rewind?
Meta acquired Limitless, the company behind the Pendant wearable and the Rewind app, on December 5, 2025. Pendant sales ended, Rewind's screen and audio capture was disabled on December 19, 2025, and service was discontinued in several regions including the European Union. People who used them for automatic capture now mostly rely on voice-first note apps instead.
Try the voice-first one
SecondBrain is free on iPhone, Android and the web. Speak once and it remembers.